The House of Lords needs to reduce the number of “passengers” who contribute little to the upper house, an issue caused in part by the mass creation of life peers under Tony Blair and David Cameron, the Lord Speaker, Norman Fowler has said.

The Thatcher-era cabinet minister who has been Speaker for the past two years is at the centre of efforts to slim down what he believes is a bloated chamber, from its current near-800 to a planned ceiling of 600.

In an interview with the Guardian, Fowler said that while the majority of peers contributed significantly to the chamber, factors such as a lack of screening for political appointees meant some new arrivals had little idea of what their role entailed.

“You do have extraordinary cases where people have come in and after a few days they’ve come to the conclusion that, actually they’re in the wrong place doing the wrong thing – or rather not doing the wrong thing,” he said. “And the last thing we want in the House of Lords is passengers.”

Blair created 374 life peers during his premiership, while Cameron ennobled 260 people – as against fewer than 40 each by Gordon Brown and, so far, Theresa May.

Asked if such an influx diluted the quality of the Lords, Fowler said: “It’s partly unfair, because there were some good people who came in. What I think is fair to say is that on that, as with other appointments, there was no process in which they came before a commission and it was explained to a prospective new peer what was involved in the job.”

Quick Guide Peers' attendance records Show Michelle Mone The lingerie millionaire, made a Conservative life peer by David Cameron in 2015, has faced calls to step down after it emerged she missed almost 90% of sittings in the last parliamentary year. Lords records show she has spoken in the chamber three times in three years, and she is not a member of any committee. Digby Jones The former CBI chief is a vocal supporter of Brexit – but does rather less in terms of shaping the nation in the Lords. Elevated in 2007 by Gordon Brown so he could be a junior business minister, Jones was initially busy in the Lords. But since 2014 he has spoken just six times. Peter Truscott The former MEP and Labour junior minister became something of a poster child for Lords reform after it emerged he had claimed nearly £57,000 in allowances and expenses in a year, during which he spoke in the chamber just three times. In 2009 he was suspended from the Lords for six months for offering to amend a bill in exchange for money. Paul Hanningfield A former Conservative council leader who was made a peer in 1998, he was jailed for nine months in 2011 for claiming almost £14,000 for overnight stays in London when he was not in the capital. Since then, he has spoken in the Lords five times, the last being in January 2016. Michael Heseltine Some argue that the patchy record of the Tory former minister – who spoke three times in 2018 – shows attendance is not everything. Lord Fowler notes that while Heseltine rarely contributed, when he did, “he made an extraordinarily good speech”, such as in recent Brexit debates. Photograph: Anita Russo/REX Shutterstock/Rex Features

As Speaker, Fowler has led efforts to reduce numbers. The process, undertaken by consensus, involves encouraging peers to retire and limiting the number of new arrivals, and is already exceeding its targets.

“I do think it is completely crazy that we have a system at the moment where the size of the House of Lords is totally open-ended,” Fowler said. “I know of no assembly in the western world, or any other world for that matter, where there isn’t a limit on the numbers. It isn’t a revolutionary thing to say.”

After a Christmas break, the Lords will be braced for another potential round of to-ing and fro-ing over Brexit legislation, as amendments shuttle between the houses.

In June this process resulted in the government making concessions on the power of MPs to shape Brexit, after a series of defeats in the upper house. However, Fowler downplayed the possible influence of the Lords: “It’s important that people don’t get over-excited about an amendment, because by the process of ping-pong it goes back, obviously, to the House of Commons.

“Last time we were told we were destroying the legislation – we didn’t destroy it at all. All that the Lords did was say: ‘Will you think again on this particular question?’ The Commons did and came to the same conclusion.

“It may be famous last words but I don’t think that it’s going to change the whole process itself. That process has got to be decided in the Commons.”

Fowler was speaking from his large corner office in the Lords, formerly used by the lord chancellor, with double-height panelled walls and views directly on to the river Thames.

It was, he said, something of a contrast to his debut as an MP in 1970. “It’s taken something like 50 years to get to an office like this. The first office I ever had, I shared it with Ken Clarke on one side, John Prescott on the other and Cyril Smith at the end. It was over Boots, the chemist. I’ve steadily come up the scale.”

Leaning in the fireplace was a poster bearing the slogan “Aids: don’t die of ignorance”, a legacy of Fowler’s tenure as heath secretary, when the HIV crisis first gained prominence.

Fowler, who has since become a celebrated champion of LGBT rights, briefly broke his political neutrality to say that equal marriage should be extended to Northern Ireland: “I think it should be a United Kingdom process. It shouldn’t be a matter of debate any more.”

For all the advances on Aids – last month the Labour MP Lloyd Russell-Moyle announced to the Commons that he was HIV positive but could live an entirely unaffected life – Fowler said it was a “total scandal” that almost a million people a year still died from the disease, mainly in poorer counties.

“When I have finished with this job, it is one of the things that I intend to return to, for the years that are left, to campaign on that,” he said.

Fowler also said some attitudes on HIV remained stuck in the past. “There has been a substantial change,” he said. “It hasn’t been total. I had the other day a peer who came up to me after a series of question before World Aids Day, and said: ‘You know, in my view it’s just all self-inflicted’. And you think: ‘Really?’”