Caroline Lucas versus Natalie Bennett.

The former is the party’s first and only MP, was leader for four years, and remains the figurehead most associated with Britain’s Green political movement. The latter is a party outsider and ex-journalist who took over the leadership in 2012.

The former has held various senior party positions, and has served as a Green MEP, since she joined the party in 1986. The latter only became a member in 2006.

The former’s recent most memorable media moment was when she was arrested among a crowd of adoring activists for protesting against fracking. The latter’s was being torn apart by Nick Ferrari on an LBC interview where she substituted saying how she would pay for her headline housing policy with apologetic coughing.

It’s unsurprising then that rumours are rumbling around Westminster that Lucas and Bennett have been clashing, and that some in the party want their old leader back. Indeed, ever since Lucas handed over the leadership three years ago, comparisons have been drawn between the two women.

The main argument is that Lucas is a more impressive media performer, and if she were leading the party now, during the so-called Green Surge, it would be far more popular than it’s already become. Some suppose she wishes she were back in charge. “I’m sure Caroline will be happy today,” grins one former senior Green politician I speak to following Bennett’s now infamous stumble through a radio interview.

But is there really a rift forming between the two, or is it simply journalists looking for a fight?

Nothing personal

One obvious temptation for the media to establish this rivalry is that they are both women. None of the other Westminster parties’ two most senior figures are women, and so the novelty of having them in charge clearly plays a part in speculation about their relationship.

“I’m concerned that because we’ve got two female leaders – two high-profile women – that the media are trying to turn it into some kind of cat fight,” a senior party figure says. “I don’t know. If it was two men, how would they operate differently?”

In reality, though insiders admit the party is strained by differences in ability and profile of the two women, there is not a straightforward clash of personalities.

When Lucas stepped down from the leadership in 2012, there were rumours that it was because she had fallen out of step with her party, that it wanted a figurehead to move it from eco-cosiness to a new socialist vanguard.

I asked Lucas about this at the time, who told me: “I thought it would be really good for someone else from the Green party to get a big national profile, to get known. It basically means our overall media impact has increased; that’s a good thing because as a small party we struggle to get what we think is our due media coverage . . . That’s why I stood down, it wasn’t through any political differences or anything like that.”

Yet I hear that even when Bennett started out as leader, and the Greens were not being grilled on a weekly basis, tensions began to form. By some well-placed accounts, the power-sharing was not a particularly forthcoming process.

“First of all, when Natalie was made leader, we all thought, ‘how the fuck is this going to work?’” a party aide admits. “How would Caroline not obsess over every single thing that was happening in the party – what Natalie was commenting on, how she was representing us?”

Indeed, I hear from a source close to Lucas’s Westminster office that following the leadership handover, the change was, “not as big as I was anticipating, I have to say, it doesn’t feel that different”.

Also, I hear from both sides that the two teams don’t speak to each other that often – rather surprising considering the election campaign is well underway. One former Lucas staffer reveals, “there was never a mention of Natalie. The only things discussed in that office are parliamentary; there isn’t much party politics at all.

“It’s all about Caroline, and what she’s doing. There’s not much communication at all between her office and Natalie’s people.”

Who polices the policy?

Although this lack of communication suggests a corresponding lack of unity behind the scenes, this has not yet morphed into a personality problem. It’s more about policy and the party’s direction.

A green lobbyist who works closely with both women says: “I really doubt there is a personal spat.”

And one party aide insists: “In terms of personality, they don’t clash – that’s been completely fabricated, I haven’t seen any of that at all between them.

“But there are policy differences,” they admit. “And if you sat them in a room and interviewed each of them about policy for long enough, you would certainly find some differences.”

A prominent policy tension is citizen’s income. This idea has long been a Green policy, but as the party has been formulating its 2015 manifesto, it has been plagued with internal wrangling.

In the first of Bennett’s handful of excruciating interviews, she struggled to tell Andrew Neil on the BBC’s Sunday Politics how her party would ensure a minimum weekly income of £72 for everyone.

Soon after, Lucas gave a calm and collected interview on the BBC’s Today programme announcing that citizen’s income would not be part of the party’s 2015 programme for government: “This is not a policy for the next general election.”

“The citizen’s income is not going to be in the 2015 general election manifesto as something to be introduced on May 8,” she said. “It is a longer-term aspiration; we are still working on it.”

After a flurry of confusion from the party’s press office, Bennett and her allies insisted a few days later that the policy would be included on the manifesto after all.

Policy back-and-forth is in no way unusual for a political party, but the citizen’s income struggle represents a wider split in how the Greens view their party’s influence and direction. Lucas’s main argument in her Today interview was that the Greens were not going to be the governing party, and therefore their function – outside of their distinctive environmental agenda – is to act as a tug to the left for the mainstream leftwing parties, ie. to put pressure on Labour.

Bennett, on the other hand, has been at the forefront of creating a full programme of proposals. The party will soon have a “fully costed” manifesto, as it attempted for the last election – though one previous Green politician laughs when I mentions this and calls it “a fantastic utopian suicide ticket”.

Current Green policies cover housing, the NHS and education policy. And when Bennett announced her priorities at the Green election campaign launch last month, climate change came second to last on the list.

Many have championed Bennett’s new direction, feeling pigeonholed as a single-issue environmental movement.

“I feel vindicated because the Green party has positioned itself on the left,” a former senior Green official tells me. “It’s not necessarily a left-wing party, but I encouraged it to be on the left because the right was so crowded and the Greens’ best chance is forming alliances with left-wing parties.

“And to be fair to Natalie Bennett, they really are now taking that space in terms of the positioning of the party.”

Breaking from the received Westminster wisdom that Lucas is the more impressive of the two, this source tells me: “I actually think there are tensions because Natalie is extremely good. Until now at least, she’s a competent, credible voice, and an alternative voice to Caroline Lucas, who I have always thought was a bit whiny. Bennett sounds less sanctimonious.”

But they add: “On the whole, the Greens have been short of talent; the [London] Assembly Members, for example, really haven’t stepped up to the plate.”

Another insider also laments the party’s lack of leadership potential, asking hopefully: “If the membership is retained, does that mean a bigger talent pool of personalities in 2020?”

Yet the traditional wing of the party is apprehensive about the Greens’ new direction. These are the committed environmental activists, thrilled by their party’s climate change agenda, and championing Lucas when she was arrested at a fracking protest in the summer of 2013. The party hasn’t been nearly as vocal about climate change recently.

A leading figure in the green lobby tells me, “I don’t see very much from them on the environment – their reasoning is that they don’t need to, that the party’s branding and name already says it all.

“Caroline has obviously done so much hard work as an MP on climate in the chamber, pushing on select committees and amendments,” they say, admiringly. “They do need more personalities like her.”

There are also those who feel let down by Bennett and her stumbling media appearances, and look back at Lucas’s leadership with green-tinted glasses.

“Caroline will be pissed off at picking up the pieces the whole bloody time,” says the high-profile green lobbyist. “Friends of mine who work for the party are very frustrated about what’s been happening; there’s a huge lack of sympathy for her misperforming.

“I mean, I’m always having to explain obscure environmental policies to people like you [journalists], with the macroeconomics to back it up, and I manage it.”

Debategate

The saga of the TV debates has done the most to trigger people pitting Bennett and Lucas against one another. But this is just as much the party's fault as a result of Bennett being a less accomplished media performer.

We recently revealed the Greens’ request for Bennett and Lucas to take one television debate each, interpreted as a bid to limit the high-profile media appearances of the former. We also broke the story that Lucas wished to take part in the debates; she said she “would be happy to do it”.

Yet at odds with the apparent wishes of both the party and Lucas, Bennett insisted on the Sunday Politics about a month ago that she alone would be doing the debates: “They’re ‘leader debates’, and I’d be doing those.”

The broadcaster rejected the Greens’ request for Lucas to take part.

“Behind the scenes, Bennett is very assertive, and she meant it when she shouted down the query about whether she would do some of the debates, and Caroline would do some,” a former senior party figure tells me. “Even though Caroline wanted to have a go – and knowing her, I assume she wants to be back in charge.”

When I ask him how the “Green surge” has affected the party, Jason Kitcat, the leader of Brighton’s Green-led council, says: “The Greens are an established part of the political spectrum; we’ve had national-level scrutiny really all along. The thing actually that has changed it has been the debate about the TV debates. That has been absolutely what has changed it.”

He says there was not “a huge debate” internally about whether Lucas or Bennett should represent the party, though admits, “there have been some noises off stage saying some unhelpful things there”.

His argument, backed up by the Green press office, is that the Greens have never been “one single national party” with one leader on whom all the focus lies. In fact, there was a period when the Greens didn’t have a leader at all. “So it’s a rational conversation to say who should speak on behalf of those parties [the Scottish Green Party, Green Party in Northern Ireland, and Green Party of England and Wales] at these debates.”

Unfamiliar territory

Another sore point is the energy being expended on Bennett’s campaign in Holborn and St Pancras. It is her home constituency, and she also contested it at the last election. Although her fortunes are slightly greater this time round, it is highly unlikely she has a chance in the safe Labour seat.

I hear from a party source that this has caused some irritation among Brighton Greens, who see little point in funnelling the party’s scarce resources into an unwinnable seat, simply because the leader chooses to stand there. The Greens now have 12 target seats, and Bennett hopes they win around half of them. Holborn and St Pancras is on that list.

The party line is that returning Lucas to Westminster is its number one priority. Yet one Green politician refers to the limited resources, saying, “I don’t think that Caroline’s campaign can have any more funding, as it stands.”

***

The splits for now are only shallow, and the Greens’ startling last-minute success in terms of polling and membership figures remains the bigger story. Bennett is likely to hold on to the leadership, and Lucas is just as likely to remain professional and supportive, as well as a popular MP.

However, signs of infighting are not necessarily a bad thing. Blair and Brown’s civil war raged throughout Labour’s most successful period in modern times, after all. Just as press scrutiny of Green policies means they’re finally being taken seriously, internal spats means they’re finally growing up as a party. As one party official quipped on the day of Bennett’s LBC interview: “So we’re getting a pasting. Welcome to the club.”