When Clive James, who is 75 and in poor health, says “the end is nigh, but not that nigh”, he’s defying gravity, as usual. It’s something he’s got rather good at lately.

About two years ago, prematurely, the world’s media gave James the last rites: with valedictory interviews, hushed bulletins, sombre satellite appearances, and Australian TV anchors flying to his doorstep. “My obituaries were so fabulous,” he twinkles in an opening gambit, “I felt more or less obliged to walk the plank.” In a spooky echo of his own last chatshow, it seemed as if he had become “the late Clive James”.

That was a dark season for a writer who instinctively prefers to shine. When we met in 2013, he was living in a kind of internal exile, from family, from wellbeing, and even from his beloved mother country. Darkest of all, he was putting the finishing touches to a translation of The Divine Comedy while suffering a fate that Dante might plausibly have inflicted on a recent admission to one of hell’s training circles: leukaemia, emphysema, and a mixed bag of carcinomas.

Clive James reads his poem Early to Bed – exclusive video Guardian

James, believing himself to be virtually defunct, co-operated with these obsequies, watched himself being “safely buried”, and then found the inevitable joke. His next volume of memoirs, he declared, would be Prelude to the Aftermath, a title he lifted from his second volume of memoirs, Falling Towards England. But then, in a cartoonish twist of fate, he wasn’t “a goner”, as he’d thought, after all. He was the Comeback Kid from Kogarah, New South Wales. This, he concedes, is “all a bit embarrassing”.

Last week, at home in Cambridge, a terraced house full of paperbacks and NHS palliatives, he met with the Observer, the newspaper that gave him his first big break back in the 1970s. With a new book of poems in the offing, the conversation defaulted to his afterlife, a subject he treats with characteristically sardonic merriment. “I’ve got a lot done since my death,” he says.

Many writers half his age and twice as fit would be thrilled to be so productive. As well as publishing his verse translation of The Divine Comedy and a collection of essays, Poetry Notebook: 2006-2014 (Picador), with another volume in the works, he has made so many “farewell appearances” (first in London and then at the Cambridge Union) that his friend, PJ O’Rourke, has advised him to “soft-pedal this death’s door stuff because people will get impatient”.

Clive James on University Challenge in 1968. Photograph: ITV/REX

Well, maybe. We are, however, obliged to report that there’s only one problem with this game plan: its star player. Vivian Leopold (aka Clive) James has not yet, apparently, tired of himself. Far from it. Some people treat the appearance of Mr Reaper with resignation, shuffling off this mortal coil as if discarding an old coat, or settling an overdue gas bill. But for James, his trip to A&E was an alarm call that perked him up no end. He responded to being in extremis with all the equanimity of a drowning man. Above all, he got serious. “I am restored by my decline,” he writes, “and by the harsh awakening that it brings.”

Ever since 1958, he has always written and published poems, with a strong bias towards entertainment. The Book of My Enemy has Been Remaindered is a classic of light verse. But suddenly, fulfilling his claim that he is “a late developer”, he had a big subject, perhaps the biggest, his own last exit. The best blooms from this late flowering will appear next month in a new collection, Sentenced to Life, a title that shows James will never miss an opportunity to flash a bit of skirt. But these poems are older, sadder and wiser, the work of a clown who has found his circus inexplicably dark.

Clive James, however, is an Australian “larrikin” with a megaton of inner resource, and whose glass is never less than half full. He says he divides his poems into “lovelies” and “funnies”, which sometimes take shape on the page so fast, he says with a laugh, “that it would be giving away a trade secret to admit how swiftly they can get written”. In Sentenced to Life, there are just two “funnies”, cabaret turns, “about death, doom and destruction”. More typically, the title poem describes “a sad man, sorrier than he can say”, who confesses that “my sin was to be faithless” and who describes seeing himself afresh “with a whole new emphasis”. Occasionally, James the poet steps back to consider himself from the point of view of a literary critic, his most reliable alter ego:

What is it worth, then, this insane last phase

When everything about you goes downhill?

This much: you get to see the cosmos blaze

And feel its grandeur, even against your will,

As it reminds you, just by being there,

That it is here we live, or else nowhere.

(from Event Horizon)

Some of these late poems have struck a chord with poetry readers. Japanese Maple went viral in 2013. Montaigne once observed that we laugh and cry at the same thing, and James is an old master at playing both sides of the street. Japanese Maple caused him some embarrassment, he says, finding the joke in his situation again. “It more or less promised that I would only live till autumn [2013]. But then autumn came – and there I still was, thinking, ‘Shucks!’”

Clive James with Russell Davies on TV culture show Think Twice, so-called because ‘there were two of us … and we would be doing quite a lot of thinking’. Photograph: ITV/Rex

Another potential source of awkwardness, to which he seems finely attuned, is the curse of sentimentality. How does he deal with that?

“You’d just better hope that you’re Puccini,” he replies, cheerfully. “Puccini spent a lot of time being told he was sentimental. To which he muttered in Italian: ‘Who gives a fuck?’. You can’t deal in feelings without running the risk of being sentimental,” he instructs. “‘Sentimental’ really means ‘an excess of feeling without sufficient cause’. I think there’s plenty of cause in my work.”

Which brings us to the central theme of Sentenced to Life, the poems written to his wife, Prue, the beloved dedicatee of the collection. This strand in the book comes with another health warning. When we last met, husband and wife were estranged and James was in the middle of a campaign for reconciliation which, characteristically, he conducted in print. The introduction to his Dante translation was more or less a love letter to Prue, who happens to be a distinguished Dante scholar. Some of the best poems in the new collection are for her, again. Balcony Scene, riffing on Romeo and Juliet, closes with this appeal:

Be wary, but don’t brush these words away,

For they are all yours. I wrote this for you.

He says he is “under sentence of execution” if he speaks of “family matters”, but it’s clear that his domestic circumstances are improving. “Negotiations continue,” he says discreetly, changing the subject.

Tom Stoppard, an old friend and longstanding fan, says that James’s poetry “is open to being under-esteemed because he is accessible”. Stoppard adds that he detects “a Graham Greene-like dichotomy between the entertainments and the more heartfelt, serious stuff. Some of his early poems should be in The Oxford Book of Light Verse. These later ones gravitate more naturally towards The Oxford Book of English Verse.” Stoppard identifies James’s melancholia as a source of inspiration: “I hope he goes on rowing against this current.” Apropos the poems addressed to Prue Shaw, Stoppard observes: “One of the most moving chords ever struck in English literature is the sound of a man falling in love with his wife.”

We don’t need to get too misty here, because the poet himself has his own splinter of ice firmly in place within. “There’s a dilemma,” he says. “I hope that she [Prue] is pleased, and I hope she likes them. But finally, the poet writes for himself. I think that what Prue likes about my poems is that they are written for myself. Maybe she thinks my ‘self’ has improved... ” A mischievous chuckle. “Careful now!” he admonishes. We tiptoe around this a bit more, and move on.

James has always had other fish to fry. He has worked in so many genres, and also sold himself to television, which paid the bills. He has no regrets about his years working inside “the crystal bucket” and strenuously denies that he squandered his talent on the tube. “Anyone afraid of what he thinks television does to the world,” he says, combatively, “is probably just afraid of the world.” In the 1980s, his TV “postcards”, he insists, were “as good as anything I’ve ever done”.

Ask him what kind of a writer he is – critic, novelist, poet, memoirist, translator, or journalist – and he’s likely to say, with earnest flippancy, that he’s running a mixed business. “In Australia,” he explains, “it’s the one shop in the suburb that sells a bit of everything: fishing line, frying pans and flypaper. It’s quite a hard thing to run.”

Part of this “mixed business”, now that he’s stepped back, for the moment, from death’s door, is the second volume of Cultural Amnesia, his compendious collection of biographical essays from Akhmatova, Borges and Camus to Wittgenstein and Zweig, provisionally subtitled “The Wrath of Darth Sith”. There are also some more “lovelies” and “funnies” in the pipeline, and maybe another volume of memoirs. Oh, and he’s fretting about getting his website (with his voluminous backlist) in order.

The phone rings. It’s Addenbrooke’s hospital, booking him to check the “wound” on his scalp. (He’s just had another carcinoma cut out.) “This stuff happens all the time,” he says, seeming temporarily lowered by the irruption of medical concern, and then returns to the conversation, with a reference to the 19th-century French novel. “As a writer, if you can arrange it,” he jokes, “it’s good to be Victor Hugo.” A beat. “I’m a natural inhabiter of the limelight,” he continues. “It’s a character weakness. I may as well treat it as a strength, but it’s a character weakness.” Speaking now of the character who haunts the pages of Sentenced to Life, he claims that he’s “the same kid who wrote Unreliable Memoirs. That kid was full of melancholy and fear, beneath a lot of self-confidence. I wouldn’t want to lose him. Maybe he’s my meal ticket.”

James at the Playboy Mansion in 1987. According to James: ‘This is the one I should never have done.’ Photograph: ITV/REX

Surely, at this late stage, as the object of so much attention, he must have a choice about how to live in the antechamber to oblivion? “That’s the strange thing. I got confined to…” He gestures round the kitchen in which we are sitting: “To my burrow, but the lights haven’t switched off.” Now he perks up again. “It’s very gratifying. The condition of most writers is to be forgotten, and while they’re alive, too. That must be tough.” He preens imperceptibly, comparing himself en passant to Madonna. “Luckily, I’m a story.”

Does he think about posterity? “Posterity?” he challenges. “It’s here. I’ve always thought that it was here. If you play to the gallery, that’s posterity. The best you can hope for is another gallery after you’ve gone, but you won’t see it. Statistically, it’s unlikely that much of what one does will be read for ever. It may just be one or two poems. For example, my Japanese Maple poem is famous among people who own a Japanese maple.”

James’s appetite for the limelight is only a small part of the explanation for the show he’s putting on in Sentenced to Life. He is too steeped in the classics to be ignorant of the Roman ars moriendi (“The Art of Dying”), advice on how to “die well”, though even he would think it bad form to refer to it. Another part, I think, is a characteristically Australian two fingers to British reticence.

Ever since he landed here in the icy winter of 1962, James has been engaged in a raucous, self-centred and highly entertaining argument with British cultural conventions, a dispute complicated by the awkward truth that he also loves British culture to bits. In the process, he virtually invented TV criticism at the Observer, infuriated the poetry establishment, and reminded the British reading public, which has always been curiously partial to the Australian voice, what could be done with the English language if you had been raised in the Sydney suburbs and had the good luck not to go to Eton or Winchester.

In short, he found a voice. For some writers, Tom Stoppard for instance, “that wonderful tone of voice was so refreshing. There was nothing else quite like it.” In consequence, Clive James has been celebrated, parodied, acclaimed, patronised, lionised and disparaged – but never ignored. He admits he’s taking an “unconscionable time to die” and reports, wryly, that Germaine Greer has briskly declared her intention, when the time comes, to make her exit with “a lot less fuss”.

James cannot help himself. In his Observer days, he became Sunday’s must-read columnist – a vertiginous mix of literary exuberance, show-off allusion, topical wisecracks and fuck-you Aussie irreverence. Who can forget his picture of the Formula One commentator Murray Walker describing every grand prix “as if his trousers were on fire”?

By the time he was appearing on What the Papers Say in 1972, James was the Observer’s TV critic. Photograph: ITV/REX

The best of James’s observations – for instance, that “Perry Como gave his usual impersonation of a man who has simultaneously been told to say ‘cheese’ and shot in the back by a poisoned arrow” or that Arnold Schwarzenegger in Pumping Iron resembled “a brown condom filled with walnuts” – had an unequalled, surreal hilarity that, in the words of Charlie Brooker, made “your brain yelp with delight”.

By the mid-70s, James had become that literary phenomenon, as rare as the hippogriff, a critic who might put Rambo and Rimbaud in the same sentence, and somehow get away with it. In fact, he’d probably done that already, and we hadn’t noticed, being too distracted by his comparison of Beowulf to Jaws or his fascination with Martina Navratilova. By his own standards, this conversation is possibly rather undernourished, merely referring, in passing (in addition to Puccini and Victor Hugo), to Byron, Brecht, Antonioni, Catullus, House of Cards, Pushkin, Jenson Button, Freud, Sartre, George Steiner, and The Ballad of Reading Gaol.

Clive James is an a omnivore, and some of his appetites have got him into trouble. “When I do die,” he wrote years ago in his memoirs, “and come to that checkpoint inside the gates of hell, it will be no secret between me and [Satan] that I suffered from an inordinate susceptibility to female beauty.” His ongoing negotiations with his wife derive from the revelation that his love for down under had included a long affair with a bottle-blonde Australian former model named Leanne Edelsten. But that was in another country and now, finally, it’s his frailty that keeps him close to Addenbrooke’s, marooned in the UK.

Like many postwar Australians, he first came to Britain to get closer to the source of a culture with which he was mildly obsessed. He claims to have followed the example of the journalist Alan Moorehead, but was otherwise simply joining the herd. “I was remarkably stupid,” he says. “I did it because everyone else did. It was as dumb as that. And when I got here I ran out of money and couldn’t go back. It was 16 years before I had enough money to get home. The Observer flew me home to do an assignment.”

With Margarita Pracatan, a regular performer on his 80s TV show. Photograph: ITV/REX

In the interim, he had gone up to Cambridge as a graduate, and discovered a taste for mixing erudition with performance. He’s been showing off ever since. Tom Stoppard cherishes this side of James. “He writes so generously about other poets,” he says. “‘Erudite’ suggests narrow and deep, but Clive is wide and deep.”

The glow of the Cambridge Footlights was not bright enough for the young autodidact, who was in a hurry. From the ivory tower, he gravitated to the pub, the Pillars of Hercules in 70s Soho, at that time the centre of New Grub Street. Here, he revelled in the patronage of three great editors: Ian Hamilton (the New Review); Karl Miller (the Listener) and Terry Kilmartin (arts panjandrum at the Observer). It was Kilmartin who commissioned the TV column that would shape his career. Of course it wasn’t just about television. “I used the column,” he says, “to analyse British culture.” Or, to put it another way, to wrestle it to the ground for a closer interrogation.

He says he is not “a natural rebel”. As an outsider, he sometimes hankers to be part of the plot, on the inside track. In the 1970s, having made friends with the mafiosi of the New Statesman (Christopher Hitchens, Martin Amis and Julian Barnes, among others), he floated the idea of reviving what FR Leavis (one of his bugbears) liked to excoriate as “the modish London literary world”, and suggested that this metropolitan cabal should meet for a regular lunch. “The fun at the time,” he remembers, “was to make it part of a conspiracy. But it really wasn’t. It was just lunch.”

The convivial, and conspiratorial, James became notorious for trailing his cultural coat with exquisite references to Pushkin and Mallarmé, allusions to Mandarin poetry, and snatches of Ovid and Catullus. He’s not lost that knack, though it has become braided more seamlessly into the texture of his late life’s work. Sentenced to Life contains a poem of homage, Compendium Catullianum, whose title was cooked up for him by his neighbour, the classicist Mary Beard. From memory now, he begins to recite some of the Latin (Catullus’s Carmen 101, written in memory of the poet’s dead brother) that inspired his own poem.

Multas per gentes et multa per aequora vectus

advenio has miseras, frater, ad inferias,

ut te postremo donarem munere mortis

et mutam nequiquam alloquerer cinerem. *

“It goes on,” he says, “to that famous last line: ‘atque in perpetuum, frater, ave atque vale [And for eternity, my brother, hail and farewell.]’.” He glances out of the window towards the Japanese maple in the garden. “I learned a lot of Latin poetry here,” he says. “That’s the great thing about a place like Cambridge. So many great minds. It’s like being in Los Alamos.”

Breaking cover in the closing poem of this collection, he admits himself to be “dying by inches”. This, more than the ironic bravura of his latest platform appearances, seems to represent the real Clive James, a writer whose commanding voice contains a constant variety of colour and tone. Regretting his frailty, he has become, he says, “the echo of the man you knew”. Momentarily sombre, he agrees that death, as much as love, is the true lyric inspiration. “I think I’m writing better now than I ever did. That’s where lyricism comes from. The love lyric is always full of approaching sadness.”

Almost wistful, he returns to talking about Australia, “the land of my youth, the land of permanent youth. I think about it all the time and,” he gestures to his laptop, “I follow it continually, too.” He adds, quite matter-of-fact, and hardly boastful, that he is “one of Australia’s much-loved sons”. Another twinkle. “That’s a category, you know.”

Clive James receives his honorary doctor of letters at the University of East Anglia in 2006. Photograph: Steve Adams, Archant Photographic

Putting aside, if he can, these areas of regret, there’s the relentless tick-tock of failing health. At least he’s in no pain. “What I’ve got doesn’t hurt. I’ve been lucky. The treatment has been benign. I don’t know if I could concentrate if I was in pain. I’ve never had to stop.” He gets his immune system rebuilt every three weeks through a process of immunoglobulin enhancement. “It’s quite restful. I sit there all afternoon. I can read a book, and even write something, while they pump in stuff through a tube.”

His leukaemia had been in remission but now, he says quietly, “it’s still there, and has just reared its head again”. A recent bone-marrow biopsy has been a sharp, unwelcome reminder of this underlying condition. “I’m about to have some more chemo,” he says, “which I haven’t had in years. I always knew that leukaemia would catch up with me.”

Is he ever moved to tears? “No.” He seems taken aback by the question. “No,” he repeats. “I’m surrounded by too much joy from my family.” One of his two daughters lives next door, with Prue nearby in the family home. “We’re a funny bunch,” he says. “We are more likely to be moved to tears by House of Cards, when my favourite reporter got pushed under a train at the start of series two.”

A small silence intercedes. “What will happen when I go?” he wonders aloud. “I don’t know.” He pauses. “I’ll be glad to be remembered at all.” Another pause. “I’ve seen some very gifted people destroy themselves.” Pause. “I’ve had a lucky life. That includes five years I didn’t expect to get.” A final pause. “I’ll be 76 this year, I think.”

Meanwhile, awaiting another rendezvous with Addenbrooke’s, he is reflecting on all the fine words that “poets and philosophers have used to mark the path into the killing ground”.

His own last lines run on:

No supernatural powers

Need be invoked by us to help explain

How we will see the world

Dissolve into the mutability

That feeds our future with our fading past:

The sea, the always self-renewing sea.

The horses of the night that run so fast.

(from Sunset Hails a Rising)

Sentenced to Life by Clive James is published by Picador (£14.99). To buy it for £11.99 click here

* Through many nations and many seas have I come

To carry out these wretched funeral rites, brother,

That at last I may give you this final gift in death

And that I might speak in vain to silent ashes.