The leaders of Azerbaijan and Armenia signed an agreement aimed at ending decades of conflict as they were hosted by President Donald Trump at the White House on Friday.
Azerbaijan's President Ilham Aliyev and Armenian Prime Minister Nikol Pashinyan shook hands after the US president described the event as "historic".
"It's been a long time coming," Trump said of the agreement, which will reopen some key transport routes between the countries and increase US influence in the region.
Azerbaijan and Armenia fought over Nagorno-Karabakh, an ethnically Armenian enclave in Azerbaijan, in the 1980s and 1990s and violence has flared up in the years since.
On Friday, Trump said Armenia and Azerbaijan had promised to stop all fighting "forever" as well as open up travel, business and diplomatic relations.
"We are today establishing peace in the Caucasus," Aliyev said. "We lost a lot of years being preoccupied with wars and occupation and bloodshed."
Pashinyan called the moment a "significant milestone" in relations between the two countries.
