London (CNN) British Prime Minister Theresa May has defended her Brexit plan and insisted that the UK will be able to strike new trade agreements with the rest of the world after it leaves the European Union.

May's comments come after US President Donald Trump added himself to the chorus of skeptics doubting her proposal -- saying it isn't clear if the agreement will allow a US-UK trading partnership.

"I think we have to take a look at seriously whether or not the UK is allowed to trade. Because you know, right now, if you look at the deal, they may not be able to trade with us," Trump said on the White House's South Lawn.

However, on a stop in Wales while selling her deal around Britain, May reiterated that the plan "clearly identifies" that the UK will have an independent trade policy, and that it had already begun discussions with Washington.

"We will be able to do trade deals with countries around the rest of the world," the Prime Minister said on Tuesday.