Azerbaijan and Armenia signed a U.S.-brokered peace agreement on Friday, during a meeting with U.S. President Donald Trump, that would boost bilateral economic ties after decades of conflict.

The deal between the South Caucasus rivals — assuming it holds — would be a significant accomplishment for the Trump administration that is sure to rattle Moscow, which sees the region as within its sphere of influence.

"It's a long time — 35 years — they fought and now they're friends, and they're going to be friends for a long time," Trump said at a signing ceremony at the White House, where he was flanked by Azerbaijani President Ilham Aliyev and Armenian Prime Minister Nikol Pashinyan.

Armenia and Azerbaijan have been at odds since the late 1980s when Nagorno-Karabakh, a mountainous Azerbaijani

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