President Trump vowed on Thursday to investigate "alleged leaks" just hours after the United Kingdom said it had stopped sharing intelligence with the U.S. related to the Manchester terror attack, over fears that information might also be leaked.

"The alleged leaks coming out of government agencies are deeply troubling," Trump said in a statement circulated by the White House. "These leaks have been going on for a long time and my administration will get to the bottom of this."

"I am asking the Department of Justice and other relevant agencies to launch a complete review of this matter, and if appropriate, the culprit should be prosecuted to the fullest extent of the law," Trump said. "There is no relationship we cherish more than the special relationship between the United States and the United Kingdom."

In recent weeks, anonymous officials have given reporters information related to private conversations Trump shared with foreign leaders, developments in a criminal investigation of Trump's campaign associates, memos written by the former FBI director and information on other sensitive issues. The resulting news stories threw the Trump administration into chaos and prompted intelligence-sharing partners to reconsider how safe their secrets would be in such a leaky environment.

Trump said the spate of "sensitive" disclosures to the media posed "a grave threat to our national security."

Attorney General Jeff Sessions said actions are already being taken to identify and punish the leakers.

"I share the president's deep concern and talked to home Secretary Rudd yesterday about this matter," Sessions said in a statement. "These leaks cannot be tolerated and we will make every effort to put an end to it. We have already initiated appropriate steps to address these rampant leaks that undermine our national security."

The president has repeatedly described leaks as "the real story" when confronted with controversies that stem from anonymous disclosures. Leaks felled his former national security adviser, Mike Flynn, in February after reporters learned Flynn had misled the vice president about the nature of his pre-inaugural contacts with the Russian ambassador.

Leaks have also revealed uncomfortable details about Trump's private conversations with the Australian prime minister, the Filipino president and two high-level Russian officials.

But although Trump and his team have sought to keep the focus on leaks and not the allegations themselves, officials had previously avoided any concrete pledges to root out leakers internally. Justice Department officials had similarly declined to specify whether the newly-appointed special counsel, Robert Mueller, has the authority to investigate alleged leaks related to his probe of Russian activities.

After Trump shared with Russian officials the details of an Islamic State plot that Israeli intelligence services had provided to the U.S., critics questioned whether leaks about the incident would deter future intelligence-sharing efforts.

British Prime Minister Theresa May was expected to confront Trump on Thursday at the NATO summit in Brussels about why information about this week's Manchester terror attack had leaked after the U.K. shared intelligence with the U.S.

White House press secretary Sean Spicer said he wasn't aware of any confrontation between May and Trump about the leaks Thursday.

"She's sitting next to him at the dinner. I don't know," Spicer told reporters.

"The president was outraged by this, that someone in a government agency would potentially leak classified information that would undermine an ongoing investigation and further compromise national security."

Trump's tough statement was a response to the U.K.'s move to limit intelligence-sharing related to the Manchester investigation.