Sutton Coldfield MP Andrew Mitchell will not be investigated by the Commons sleaze watchdog over his apparent involvement with a cocoa magnate who had donated £40,000 to his office.

Mr Mitchell, Secretary of State for International Development, had been reported to the Parliamentary Standards Commissioner by a Labour MP over claims he helped businessman Anthony Ward to overturn a trading ban imposed on his firm in Ghana.

But the Commissioner John Lyon has announced he will not be proceeding with an inquiry.

The Sunday Times reported that Mr Mitchell phoned the British high commissioner in Ghana asking the country to lift a trading ban on British firm Armajaro Holdings.

His officials also contacted the Foreign Office to say that the partial ban on the firm - imposed amid allegations that one of its contractors had been smuggling cocoa - required “urgent attention”.

Foreign Office minister Henry Bellingham subsequently lobbied the vice-president of Ghana on behalf of the company.

Armajaro Holdings had donated £40,000 to Mr Mitchell’s political office while the Conservatives were in opposition. The money was used partly to fund the MP’s visits to developing countries.

Mr Mitchell apparently stepped in after businessman Andrew Ward, Armajaro’s co-founder, approached him for help.

Earlier this year Mr Ward cornered a big chunk of the global cocoa market, earning the nickname ‘Chocfinger’. He is estimated to be worth £36 million.

Labour MP John Mann referred the case to the Commons watchdog.

But a spokeswoman for Mr Lyon said: “He has received an e-mail about Mr Mitchell but there is no inquiry.”

A spokesperson for the Department for International Development said: “The letter from Armajaro was dealt with in accordance with normal ministerial procedures and it was immediately made clear that the Conservative Party had previously received donations from the company, as the documents released under FOI make clear.

“The matter was referred to the Foreign and Commonwealth Office through the normal channels.”