Former Soviet republics Armenia and Azerbaijan have been in dispute over the Nagorno-Karabakh region for decades. The area is internationally recognised as part of Azerbaijan, but controlled by ethnic Armenian forces. There have been regular battles near the border since a 1994 ceasefire. Both countries accuse each other of triggering the latest artillery bombardment and drone attacks north of the disputed region. Azerbaijan’s President Ilham Aliyev has sacked the foreign minister, accusing him of ‘meaningless negotiations’ with Armenia. Can the two sides resolve decades of animosity?