Incoming secretary of state John Kerry has urged his Senate colleagues to put aside their differences in the interests of presenting a strong, united front to the world.

Washington - Incoming secretary of state John Kerry warned his Senate colleagues on Wednesday that they must not allow political stalemates at home to weaken the United States abroad.

“My credibility as a diplomat and ours as a country is determined a great deal by what happens in this capital city,” Kerry told the chamber in a farewell address after being confirmed on Tuesday as the next secretary of state.

He said the way to avert a US decline was “to demonstrate that we can get our economic house in order because we can be no stronger abroad than we are here at home”.

Reflecting on his 28 years in the Senate, Kerry called for co-operation across party lines and decried intense partisanship that has paralysed Congress in recent years.

“It's our own procrastination and outright avoidance of difficult choices that threatens our own future,” he warned.

Secretary of State Hillary Clinton is due to step down on Friday, when Kerry will be sworn into office. - Sapa-dpa