Westminster sleaze watchdogs have ruled out an inquiry into shadow chancellor George Osborne's inks with a Russian oligarch.

A complaint was made to Parliamentary Standards Commissioner John Lyon over Mr Osborne's contacts with Oleg Deripaska but it has been dismissed.

A spokeswoman for Mr Lyon said: "The Commissioner has received a complaint about Mr Osborne and he has not accepted it."

The decision comes after Mr Osborne attempted to draw a line under the Tory donation furore by admitting he had made "a mistake".

He acknowledged his involvement in discussions with Mr Deripaska "did not look very good".

He said: "I neither asked for money nor received any and I didn't break any rules but I think I did make a mistake."

Earlier, the European Commission knocked back calls for a probe into Peter Mandelson's contacts with the billionaire.

Officials in Brussels said there was still "no evidence" suggesting the new Business Secretary had breached rules on conflicts of interest during his four-year stint as trade commissioner.

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