A Republican congressman was forced to backtrack quickly today after claiming the Russians had hacked into the Republican National Committee computers.

Shortly after Michael McCaul, chairman of the House Homeland Security Committee, made the claim, the RNC denied it and the congressman later told CNN he misspoke.

"The Russians ... basically have hacked into both parties at the national level. And that gives us all concern about what their motivations are," McCaul told CNN in an interview.

The Republican National Committee's communications director, Sean Spicer, quickly pushed back on McCaul's comments, saying on Twitter that "there has been no known" breach of Republican networks.


Shortly thereafter, CNN.com posted a statement from McCaul clarifying his remarks.

"I misspoke by asserting that the RNC was hacked. What I had intended to say was that in addition to the DNC hack, Republican political operatives have also been hacked," said McCaul, a US representative from Texas.

Reuters reported last month that hackers had targeted the computer systems of Republican Party organisations and Republican presidential nominee Donald Trump.

The head of the Democratic National Committee, Donna Brazile, said yesterday the organisation had been hacked by Russian state-sponsored agents who were trying to influence the November 8 US presidential election.

Debbie Wasserman Schultz resigned as DNC chair on the eve of July's Democratic National Convention after WikiLeaks published a trove of hacked DNC emails that showed party officials favouring eventual nominee Hillary Clinton over US Senator Bernie Sanders during the party's nominating contests.

- Reuters, AAP