Armenian Prime Minister Nikol Pashinyan and Azerbaijan's longtime President Ilham Aliyev were in Washington for what Trump had touted as a "historic peace summit."

"Armenia and Azerbaijan are committing to stop all fighting forever, open up commerce, travel and diplomatic relations and respect each other's sovereignty and territorial integrity," Trump said.

Trump also said he was lifting restrictions on military cooperation with Azerbaijan.

The fine print of the deal was not immediately available, but it joins a growing list of US-brokered initiatives for which the president believes he should win a Nobel Peace Prize.

"Many Leaders have tried to end the War, with no success, until now, thanks to 'TRUMP,'" the president boasted on his Truth Social website.

Christian-majority Armenia and Muslim-majority Azerbaijan have feuded for decades over their border and the status of ethnic enclaves within each other's territories.

The former Soviet republics went to war twice over the disputed Karabakh region, which Azerbaijan recaptured from Armenian forces in a lightning 2023 offensive, sparking the exodus of more than 100,000 ethnic Armenians.

- 'Trump Route' -

The two countries agreed on the text of a comprehensive peace deal in March, but Azerbaijan has since outlined a host of demands -- including amendments to Armenia's constitution to drop territorial claims for Karabakh -- before signing the document.

Pashinyan has announced plans for a constitutional referendum in 2027, but the issue remains deeply divisive among Armenians.

White House spokeswoman Anna Kelly, in a briefing with reporters on Friday, said the two countries would sign a "joint declaration" establishing a transit corridor between Azerbaijan and its exclave of Nakhchivan, a longstanding demand of Baku.

The United States will have development rights for the corridor, dubbed the "Trump Route for International Peace and Prosperity" (TRIPP), she said.

The two nations were due to sign a letter officially requesting the dissolving of the Minsk Group, a now defunct mediation body under the Organization for Security and Cooperation in Europe (OSCE), Kelly added.

The White House did not elaborate on how Friday's agreement aligns with the broader comprehensive deal.

- Nobel? -

Both countries were also expected to sign bilateral economic deals with the United States.

"Armenia walks out of this with an enormous strategic commercial partner, probably the most enormous and strategic in the history of the world: the United States of America," a White House official said.

"The losers here are China, Russia, and Iran," he said, speaking on condition of anonymity.

Trump has repeatedly praised his own diplomatic efforts to help halt deadly conflicts, notably between Cambodia and Thailand, and arch-foes India and Pakistan.

At the White House, Armenia and Azerbaijan's leaders suggested sending a joint appeal to the Nobel committee to award Trump the Peace Prize.

"Because from the leaders of the countries which were at war for more than three decades having this historic signature here, it really means a lot," Aliyev said.

On Thursday, Cambodia's prime minister announced he had nominated Trump for a Nobel Peace Prize.

Months of efforts have however yet to solve the ongoing Russia-Ukraine war and the hunger plaguing Gaza during Israel's offensive.

A deal to normalize ties between Armenia and Azerbaijan would be a major breakthrough in a region where Russia, the European Union, the United States and Turkey all jostle for influence.