British Prime Minister Theresa May told business leaders in Davos on Thursday that countries must not start pulling in different directions on trade.

She added that the World Trade Organisation must go further in its reforms.

"Too often our rhetoric in support of free trade here in Davos is not matched by our actions," she said.

"The World Trade Organisation still needs to go much further in its reforms, ensuring its rule book keeps pace with developments in the global economy."

While in Davos, May and US President Donald Trump discussed finalising the details of his first visit to Britain later this year.

More than a year into his presidency, Trump has yet to visit London and many British voters have promised that if he comes to Britain they would protest against a man they see as opposed to their values on a range of issues.

Trump's cancellation of a trip to Britain this month had raised questions in Britain over the relationship between Washington and its traditionally closest ally in Europe.

The two leaders discussed Brexit, Iran, and worries that jobs could lost at Canadian plane-maker Bombardier's factory in Northern Ireland due to a trade dispute with Boeing Co.

May was the first foreign leader to visit Trump after his inauguration last January and was filmed emerging from the White House holding hands, but a series of disagreement have since occurred.

British officials have been dismayed by some of Trump’s pronouncements, particularly a proposed ban on Muslims entering the United States and most recently when Trump rebuked May on Twitter after she criticised him for retweeting British far-right anti-Islam videos.