By Wiktor Szary 

LONDON--British Prime Minister Theresa May said she would talk about trade and security when she meets with U.S. President Donald Trump next week, but won't be afraid to challenge him on issues she finds unacceptable.

Mr. Trump will host Mrs. May at the White House on Friday, his first meeting with a foreign leader since taking office, the White House said Saturday.

"We'll have an opportunity to talk about our possible future trading relationship but also some of the world challenges that we all face," Mrs. May told the British Broadcasting Corp., citing terrorism, the Syrian conflict and the importance of the North Atlantic Treaty Organization, which Mr. Trump has called obsolete, as examples.

While the U.K. voted to leave the European Union last year, the government won't be able to sign any new bilateral trade deals until it has withdrawn from the bloc. It is free, however, to scope out possible agreements before then. Mrs. May has said she plans to trigger the formal two-year process for leaving the EU by the end of March.

Mr. Trump has spoken out in favor of the U.K.'s departure from the EU, saying "Brexit is going to end up being a great thing."

When asked if she would directly raise the issue of Mr. Trump's treatment of women, Mrs. May said: "First of all, I've already said that some of the comments that Donald Trump has made in relation to women are unacceptable, some of those he himself has apologized for."

Mr. Trump has in the past been criticized for making derogatory remarks about women. Widespread protests were held the day after his inauguration Saturday, spearheaded by women's rights activists.

"When I sit down, I think the biggest statement that will be made about the role of women is the fact that I will be there as a female prime minister of the United Kingdom, talking to him, directly talking to him about the interests that we share."

Pressed on the point, Mrs. May said that whenever there is something she finds unacceptable, she won't be afraid to say so to Mr. Trump.

Write to Wiktor Szary at Wiktor.Szary@wsj.com

(END) Dow Jones Newswires

January 22, 2017 08:54 ET (13:54 GMT)