Turnbull avoids Joyce, gun questions in DC

Prime Minister Malcolm Turnbull has sidestepped questions about embattled deputy prime minister Barnaby Joyce and America's raging debate on gun control.

Mr Turnbull, speaking outside the White House in Washington DC on Thursday (Early Friday AEDT), had just left a meeting with US Secretary Steven Mnuchin and said the talks proved President Donald Trump's recent company tax cuts underlined the benefit of Australia completing its own tax reform program.

Asked if he still supported Mr Joyce as deputy prime minister, Mr Turnbull said: "These are matters for the leadership of the National Party".