Washington: US President Donald Trump said Friday he felt sorry for British Prime Minister Theresa May, who has resigned after three years of turmoil surrounding her country's "Brexit" from the European Union.

"I feel badly for Theresa. I like her very much. She is a good woman," Trump told reporters on the White House lawn as he prepared to set off on a trip to Japan.

"She's a good woman. She worked very hard. She's very strong," Trump said.

Trump has nonetheless criticized May repeatedly in recent months for her handling of Brexit even as she tried to establish good relations with him.

The US leader is scheduled to make a state visit to Britain next month and will meet with May just days before her final day in office, which is June 7.