YEREVAN, Sep 7 (AFP) - Armenia on Thursday (Sep 7) accused arch-foe Azerbaijan of preparing a "fresh military provocation" by massing troops on their border and near the breakaway Nagorno-Karabakh region.

The ex-Soviet republics have been locked in a decades-long conflict over the mostly Armenian-populated region of Nagorno-Karabakh inside Azerbaijan which is controlled by separatists.

Tensions have escalated sharply in recent months as each accuses the other of cross-border attacks.

"The military-political situation in our region has seriously worsened," Prime Minister Nikol Pashinyan told his cabinet meeting in Yerevan.

He said Azerbaijan was "concentrating" troops on the border and also near the mountainous Karabakh region.

"Azerbaijan is demonstrating its intention to undertake a fresh military provocation against Nagorno-Karabakh and Armenia," Pashinyan said.

Azerbaijan denounced the claims as "yet another false political manipulation."

"Armenia must abandon territorial claims to Azerbaijan, to end military-political provocations, and to stop creating obstacles to the peace process," its foreign ministry said in a statement.