A Labour MP being investigated by the Parliamentary Commissioner for Standards for claiming over £100,000 in allowances for his second home is stepping down.

Harry Cohen, who says he is the most professional MP his constituents have ever had, including Winston Churchill, will go at the next general election. Party workers of his Leyton and Wanstead constituency in East London were informed last week.

Sources close to the party say that after 26 years representing the constituency he wanted to spend more time with his wife who is in poor health. He maintains that he will be exonerated by the commissioner over his expenses claims.

Mr Cohen has claimed more for his second home than any other MP in outer London - £104,000 over six years - despite his constituency being a journey of around half-an-hour by Tube to Westminster.

He received the Additional Cost Allowance of £104, 701 between 2002 and 2007 for his constituency home in Wanstead.

Mr Cohen, a career backbencher since he was first elected in 1983, declares his main family home as being in Colchester, Essex. It is a 200-year-old listed converted school with a 26ft lounge.

He has previously said: "I am almost certainly the most professional MP Leyton and Wanstead has ever had, and that includes Winston Churchill."

Part of his seat was in the East London constituency that Churchill represented from 1945 to 1964.

Mr Cohen’s expenses have been under scrutiny since MP claims were first made public in 2004.

Then the Leyton MP claimed £123,718 in allowances for the year 2003-2004 on top of his salary of £57,485.

Two years later Mr Cohen was again one of London’s most expensive MPs. He claimed the maximum Additional Costs Allowance of £21,634 and his total expenses amounted to £128,881, in addition to his then salary of £59, 686.

Mr Cohen has said he cleared his arrangements with the House of Commons authorities.

He said the Colchester property was his "family home". He said that there was no reason under the Commons rules why London MPs should not live outside the capital and have a second home in their constituency. "It is the legitimate costs of having a constituency home to do my job. We don't have a system where people are required to live in their constituency," he said.

"I am doing nothing wrong whatsoever. I am using it for parliamentary purposes. It is a legitimate and proper use of it."

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