The head of a key US congressional investigation into alleged Russian hacking has temporarily stepped down amid an ethics inquiry into him.

House Intelligence Committee chairman Devin Nunes is now himself under investigation by the House Ethics Committee.

The panel is looking into claims that the Republican disclosed classified intelligence.

Mr Nunes called the charges "entirely false" and "politically motivated".

Representative Mike Conaway will take control of the Russia investigation.

Mr Nunes said his decision came after "several leftwing activist groups have filed accusations against me with the Office of Congressional Ethics".

He added he would continue to fulfill his other responsibilities as chairman and has requested to speak to the Ethics Committee "in order to expedite the dismissal of these false claims".

Democrats have criticised Mr Nunes for his handling of the inquiry, which is also looking at possible links between the Trump campaign and Moscow.

House Speaker Paul Ryan said he fully supported Mr Nunes' decision.

Mr Ryan said he trusts Mr Nunes, describing him as "eager to demonstrate to the Ethics Committee that he has followed all proper guidelines and laws".

But he added that the inquiry "would be a distraction" for the House Intelligence Committee's investigation.

(Source: BBC)