Donald Trump will travel to London for a meeting of NATO heads of state in December.
NATO Secretary General Jens Stoltenberg announced the event on Wednesday.
He said: "The meeting in London is an opportunity for Allied leaders to face up to current and future security challenges and to ensure that NATO continues to adapt to its population of nearly one billion people keep people safe. "
It is the 70th anniversary of NATO.
The last time Trump visited the UK, he distracted London from fierce protests over his visit due to security concerns.
This year he will be able to make fewer detours.
The Press Association had received figures earlier this week suggesting that Mr Trump's last visit to the United Kingdom cost £ 14.2 million.
The protests included a large inflatable dinghy that looked like it was going to look Baby trumpthat flew over the entire march.
Theresa May said in a statement: "The UK is one of the founding members of NATO, and I am delighted that the Secretary General has asked us to hold a meeting of NATO leaders this year on the occasion of his 70th birthday.
"For 70 years, NATO has been the cornerstone of our national security, but the challenges of today are very different from those we faced when the Alliance established its first headquarters in London.
"The UK has played a central role throughout NATO's history, as it has adapted to new and complex threats to our security.
"As we pay tribute to the servants and women who have been working so hard to protect us for many years, the December meeting is an important opportunity to identify the steps we need to take now to achieve this To modernize the Alliance and ensure its continued success. "
NATO has not yet confirmed a place and date for the meeting.
The announcement came when Macedonia made an important step in joining NATO by signing the accession protocol.
Greece has blocked the country's accession attempts for more than a decade because of name disputes.
The protocol must be ratified by the 29 members. Macedonia will call itself North Macedonia to avoid confusion with the Greek administrative territory of the same name.