Donald Trump is “100 percent behind” NATO, Britain’s Prime Minister Theresa May has said, after becoming the first foreign leader to meet the US president since he was sworn in a week ago.

In a joint press conference after a White House meeting on Friday, May said that during their talks Trump gave strong backing to NATO, an alliance that he had previously called “obsolete“.

The two countries “are united in our recognition of NATO as the bulwark our collective defence, and today we’ve reaffirmed our unshakable commitment to this alliance,” she told reporters.

The meeting between the two leaders in Washington, DC, came a day before Trump is scheduled to speak by telephone to Vladimir Putin, his Russian counterpart.

When asked about his upcoming discussion with the Russian president, Trump said he wanted to have good relations with Russia but played down any talk that he was ready to lift US sanctions against Moscow.

“We’ll see what happens as far as the sanctions – very early to be talking about that,”  Trump said, adding that he hoped to have a “fantastic relationship” with Putin, but noted it was possible that would not occur.

“Trump doubled down on his statements that he does not know Putin, that he does not have a relationship with him, but he believes that if it is a positive relationship between the two countries then that certainly would be of benefit to the US,” Al Jazeera’s Kimberly Halkett, reporting from Washington, DC, said.

For her part, May took a sterner line, insisting that Putin must live up to the Minsk Agreements that would put an end to Russian military interference in Ukraine.

‘Brexit a wonderful thing’

May arrived in the US on Thursday at a time when the UK is in the process of quitting the European Union, or Brexit.

Faced with withdrawal from the European single market, the British government is scrambling to secure bilateral deals around the world.

May said that a trade deal between Britain and US was “in the national interest in both our countries”, while Trump threw his weight behind Brexit, saying it would be a “wonderful thing” for the UK.

“I think when it irons out, you’re going to have your own identity, and you are going to have the people that you want in your country,” Trump said.

“You’re going to be able to make free trade deals without having somebody watching you and what you are doing.”

Focus on torture

Ahead of their White House meeting, May had tough words on Trump’s assertion that torture “absolutely” works, telling reporters that she condemned the use of illegal interrogation.

Trump’s views on torture have raised concerns that he will try to reverse laws put into place by predecessor Barack Obama outlawing the brutal interrogation techniques like waterboarding used by the CIA on suspects following the September 11, 2001 attacks.

When asked about the use of waterboarding as an intelligence-gathering tool, Trump said he would defer to Defence Secretary James Mattis regarding the practice – even though he said he still believes it is effective.

Trump said Mattis does not “necessarily believe” in waterboarding and other enhanced interrogation techniques, which many politicians and other rights groups denounce as torture.

Mattis “will override because I’m giving him that power,” Trump told reporters. “He is an expert. He is highly respected.”

‘Mexico made us look foolish’

Trump’s first week in office has been marked by a war of words with Mexico over the building of a border wall, and his vow to make Mexico pay for it.

On Thursday, Mexican Enrique Pena Nieto called off a planned trip to Washington in protest.

READ MORE: Trump to Mexico leader – ‘Pay for wall or stay away’

During the press conference, Trump said he had a “very good” phone call with Pena Nieto on Friday and that the two had agreed to work to improve ties.

“We had a very good call. I have been very strong on Mexico. I have great respect for Mexico … but, as you know, Mexico with the United States has out-negotiated us and beat us to a pulp through our past leaders.

“They’ve made us look foolish,” Trump told a news conference at the White House.

Trump said the call was friendly and he looked forward to renegotiating the US trade relationship with Mexico in the future.

Source: Al Jazeera and news agencies