MPs will hold an emergency debate today, days on from a dramatic U-turn which saw an politician accused of breaking lobbying rules lose his job.

Owen Paterson resigned and the government's plans to reform Westminster's disciplinary procedures were left in tatters after Conservative MPs voted against the proposal of the Parliamenary Commissioner for Standards.

Despite Dame Andrea Leadsom's amendment to delay a decision on Mr Paterson's case until a new committee was formed gained enough support to pass the Commons, a public outcry last week saw the government quickly reverse their decision.

Among those who were forced to defend themselves for backing the Leadsom amendment were Basingstoke MP Maria Miller and North West Hampshire MP Kit Malthouse.

On Monday, MPs will take part in an emergency debate in the House of Commons secured by the Liberal Democrats, with MPs warned to avoid a rush to rewrite the rule book.

Labour leader Sir Keir Starmer has called on Boris Johnson to apologise to the nation as renewed charges of Tory “sleaze” threatened to engulf his administration.

Ministers were accused of seeking to rewrite the rule book after Mr Paterson – a Conservative former Cabinet minister – was found to have repeatedly lobbied ministers and officials on behalf of two companies he worked for as a paid consultant.

The attempt failed after opposition parties refused to co-operate, while Mr Paterson announced he was quitting as MP for North Shropshire blaming the “cruel world of politics”.

He has insisted throughout that he did nothing wrong.

While ministers have acknowledged it was a mistake to conflate his case with efforts to change the system, they argue that there is still a need for reform.

In particular they have pointed to concern among some MPs about the need for a more robust system of appeals when they are found to have breached the rules.

However Chris Bryant, the Labour MP who chairs the cross-party Commons Standards Committee which found Mr Paterson guilty of an “egregious” breach of the ban on paid lobbying by MPs, cautioned against a rush to change.

He said Mr Paterson had had a “very fair hearing” by the independent Commissioner for Standards Kathryn Stone and had been found “bang to rights”.

Mr Bryant said the Government should not become involved in Commons disciplinary procedures which were a matter for MPs.

“I don’t think we should leap into making sudden changes. One of my principles is that the Government should stay clear of independent disciplinary processes,” he told Sky News.

“We agreed that he (Mr Paterson) had broken the rules, not just once but on 14 occasions, and it saddened me that the Government got this completely and utterly wrong.”

Responding to public outcry last week, government minister Mr Malthouse 

said that the issue of Mr Paterson is completely separate from the need for review, which is what she voted for.

He said: "I raised concerns before the controversial standards vote this week about the conflation of two issues making the issue a challenging one for all members. First, the very real problems and need for reform of the process for investigating and adjudicating on MP’s conduct, not least the lack of any appeal process, and second the individual case of Owen Paterson.

“In the event, the amendment on which I voted sought only to pause the action against Mr Paterson, not exonerate him, while seeking reform of the process, and on that basis I voted for it in line with the government of which I am a part.

“Subsequently I again raised my serious concerns along with those of the many constituents who wrote to me, and what ensued speaks for itself.

“Through all this furore, I do feel for for Mr Paterson, who whatever the conclusion about his conduct, has now lost his wife to suicide and his position as an MP as a result of a process that has no possibility of appeal."

Meanwhile, Mrs Miller has said that the issue of Mr Paterson is completely separate from the need for review, which is what she voted for.

She told the Gazette: “I voted for a complete review of the system to investigate allegations against MPs because the process is out of date, lacking any independent appeal system.

“The need for this review is completely separate to the situation faced by Owen Patterson and the two should not be conflated.

“This is an opportunity to call for important changes to be made to modernise the way Parliament works.”

The debate is due shortly after the House starts sitting at 2.30pm.