British Prime Minister Boris Johnson on Monday rejected pressure to appear at an emergency debate on parliamentary standards, where he was accused of leading his party "through the sewers" following days of sleaze claims.

The debate was held as calls mounted for an independent inquiry into allegations of apparent corruption and inappropriate conduct within the Conservative party and government.

Last week the government caused outrage by trying to overhaul parliament's internal disciplinary process, which would have prevented the 30-day suspension of a Tory MP found to have committed an "egregious" breach of lobbying rules.

Prime Minister Boris Johnson faces calls to apologise
Prime Minister Boris Johnson faces calls to apologise UK PARLIAMENT / JESSICA TAYLOR

Although Johnson abandoned the unprecedented move within 24 hours -- prompting the lawmaker, Owen Paterson, to resign from parliament -- it threw the spotlight on a raft of allegations around MPs' behaviour.

Standing in for Johnson at Monday's debate, senior minister Steve Barclay apologised on behalf of the government for "the mistake made last week".

"We recognise there are concerns across the House (of Commons) over the standards system... yet while sincerely held concerns warrant attention, the manner it approached last week's case conflated it with an individual case," he added.

Former environment secretary Owen Paterson was accused of 'egregious' lobbying on behalf of two firms that paid him £100,000 a year on top of his MP's salary
Former environment secretary Owen Paterson was accused of 'egregious' lobbying on behalf of two firms that paid him £100,000 a year on top of his MP's salary AFP / Tolga AKMEN

Opposition Labour leader Keir Starmer slammed Johnson for not having "the decency to come here, either to defend what he did or apologise for his actions.

"When required to lead he's chosen to hide. His concern is self-preservation, not the national interest," he added.

"He led his party through the sewers and the stench lingers. He is not a serious leader and the joke isn't funny any more."

Johnson said he would miss the emergency debate because of a longstanding engagement at a hospital
Johnson said he would miss the emergency debate because of a longstanding engagement at a hospital POOL / Peter Summers

Last week's actions also prompted an extraordinary broadside from former Conservative prime minister John Major, who called the episode "shameful" and "had the effect of trashing the reputation of parliament".

An Ipsos MORI survey for the London Evening Standard newspaper indicated that the popularity of Johnson and the ruling party were falling even before the scandal.

The Tories trailed Labour in the poll while a majority of adults disagreed that Johnson has what it takes to be a good prime minister for the first time since he came to power in 2019.

Prime Minister Boris Johnson sent senior Cabinet colleague Steve Barclay to parliament to face down angry MPs
Prime Minister Boris Johnson sent senior Cabinet colleague Steve Barclay to parliament to face down angry MPs PRU / -

Despite the crisis, Johnson was in northeast England Monday to see hospital staff receive Covid-19 boosters and flu jabs, in what he called "a longstanding engagement".

His spokesman noted he would make the roughly 600-mile (965-kilometre) round-trip by train -- days after being heavily criticised for flying by private jet from the COP26 climate summit in Glasgow to attend a private London dinner with former colleagues at the Daily Telegraph newspaper.

"What we do need to do is look also at the process, and that is what we were trying to do last week," Johnson said during a brief media appearance at the hospital, insisting he would now focus on a cross-party approach to reforms.

The furore around MPs' conduct heightened over the weekend with a report the Conservatives have been "systematically" awarding seats in the unelected House of Lords, parliament's upper chamber which scrutinises legislation, to its high-value donors.

An investigation by The Sunday Times and Open Democracy found almost all of the party's 16 different treasurers over the past two decades were offered seats after increasing their donations to more than ?3 million ($4.1 million, 3.5 million euros).

It follows other claims of government wrongdoing over the awarding of coronavirus contracts and multiple aspects of Johnson's own conduct, as well as renewed focus on lawmakers being able to have high-paying second jobs.

Paterson himself was found to have repeatedly lobbied ministers and officials for two companies paying him more than ?100,000 a year.

"There are definitely conflicts of interest that need to be considered," Liberal Democrat MP Wendy Chamberlain, a former policewoman who applied for Monday's urgent debate, told BBC radio.

She later told parliament: "They say a fish rots from the head down and I'm disappointed to see that the PM has decided not to turn up today to answer questions."

Her party has demanded a public inquiry into sleaze and corruption allegations, which would have the power to summon witnesses and take evidence under oath.