Stephen Byers facing parliamentary lobbying inquiry
Stephen Byers in a secret video recorded by Channel 4 Dispatches
Ex-Transport Secretary Stephen Byers has asked for an investigation into claims that he worked for companies to secure secret deals with ministers.
He said he hoped standards watchdog John Lyon would find he had "complied with MPs' code of conduct" and "fully disclosed" his outside interests.
Mr Byers was secretly filmed saying he was a like a "cab for hire", but later said he had "exaggerated".
Downing Street has ruled out a separate government inquiry into the claims.
Former Labour ministers Geoff Hoon and Patricia Hewitt were also secretly filmed for the joint investigation for The Sunday Times and Channel 4's Dispatches programme. They, and Mr Byers, deny any wrong-doing.
Conservative leader David Cameron has said Prime Minister Gordon Brown should initiate an investigation.
He said of the allegations against Mr Byers: "I think what it shows is a party that has been in power for far too long and has lost touch with what it's meant to be doing."
But a Downing Street spokesman said: "The PM is of the view that Byers has done the right thing by referring himself to the parliamentary authorities".
In a statement, Mr Byers, MP for North Tyneside and also a former trade secretary, said: "I have this morning referred myself to the standards commissioner, John Lyon, and asked him to investigate my actions.
"I am confident that he will confirm that I have complied with the MPs' code of conduct and have fully disclosed my outside interests."
Mr Byers claimed to an undercover reporter that he had quietly engineered a deal with Transport Secretary Lord Adonis over the termination of a rail franchise contract.
The firm involved, National Express, told the BBC it had paid no money to the former minister and had only spoken to him in his capacity as an MP for a constituency on the "eastern side of the country".
Mr Byers also claimed his intervention on behalf of Tesco had got Business Secretary Lord Mandelson to change regulations on food labelling.
But a spokesman for the supermarket said: "We did not speak to Mr Byers on food labelling, regulation or indeed any other issue. These claims are completely fictitious and Mr Byers has acknowledged this to us."
The business and transport departments issued statements denying Mr Byers' claims to an undercover reporter that he had secured secret deals with ministers.
And Downing Street said there was "no need for an inquiry if the two departments say there has been no impropriety... the statement from the two departments could not be clearer and there is no hint of impropriety".
Commons leader Harriet Harman will make a statement about "paid advocacy and lobbying" to MPs on Monday afternoon, while Lord Adonis will have to face questions from the Conservatives in the House of Lords.
Sitting MPs are not banned from working for corporate clients but the practice is controversial
They must declare any payment in the register of members' interests
Any paid work taken by an ex-minister within two years of leaving office must be cleared by a panel - the Advisory Committee on Business Appointments
They are not allowed to table amendments or vote on bills in exchange for payment
They are normally banned for 12 months from becoming lobbyists in their specialist fields
Labour, the Tories and the Lib Dems all say they want the rules tightened to prevent ex-ministers exploiting their contacts for private gain
Mr Byers was recorded as saying he was like a "cab for hire" who would work for up to £5,000 a day, could get confidential information from 10 Downing Street and was able to help firms involved in price-fixing get around the law.
He later said he had completely overstated his case and had never lobbied the ministers, who have also issued denials.
Ms Hewitt, a former health secretary, said she "completely rejected" the suggestion she helped obtain a key seat on a government advisory group for a client paying her £3,000 a day.
She said the role she had been discussing would only have been taken up after she stepped down as an MP at the next election.
Former defence secretary Mr Hoon reportedly offered to lead delegations to ministers, and said he wanted to make use of his international knowledge and contacts in a way that "frankly makes money". He said he charged £3,000 a day.
Following the reports, Mr Hoon said he had made clear during an "informal chat" with what he assumed was "a reputable American company" that he would not lobby government or "attempt to sell confidential or privileged information arising from my time in government". He said he had not broken any rules.
For the Conservatives, shadow leader of the Commons Sir George Young told BBC Radio 4's Today programme: "I think it is quite wrong that contacts and knowledge gained when you are a minister should then be used for private gain."
'Beyond the grave'
Labour said it now wanted a statutory lobbying register, which would list details of meetings between lobbyists and decision-makers - something called for last year by the Commons public administration committee to increase transparency, but rejected at the time.
Education minister Kevin Brennan said: "I don't know if Stephen Byers was trying to big himself up in some way".
He added that large companies did not need the services of lobbying firms, as they could "talk to the government... any time they like".
The Liberal Democrats have called for a reform of the "whole rotten system". Spokesman Norman Baker told BBC Radio 4's World At One: "This isn't simply about Stephen Byers, it's not even just about National Express, it's also about the ability of ex-ministers to influence from beyond the grave, as it were, departments apparently to the detriment of taxpayers."
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