Azerbaijan and Armenia agree to ceasefire in Nagorno-Karabakh

• The Russian-brokered agreement also says that the Azerbaijani and. Armenian officials will begin "substantive negotiations" with the aim of resolving the conflict as soon as possible.

The big picture: Hundreds of soldiers, including 376 Armenian troops, have been killed since the recent fighting began in late September, per the NY Times. Azerbaijan has not disclosed how many of its soldiers have died.

• The UN estimates at least 58 civilians have also been killed, the Times added.

The backstory: Nagorno-Karabakh is a mountainous region of around 150,000 people that is populated mainly by ethnic Armenians but lies within the borders of Azerbaijan. The countries have both claimed the territory since the collapse of the Soviet Union, fought a war over it from 1992-1994, and stood on the precipice of further conflict since.

• The recent violence is the worst the region has seen since 2016, and began with coordinated air and missile attacks late last month from Azerbaijan, which claimed Armenian forces had been preparing an attack (Armenia denies that).

• Previous skirmishes, though numerous, have left the stalemate largely unaltered. So has a peace process overseen by the U.S., France and Russia.