A Ukrainain seviceman attends military drills near Urzuf village not far from the city of Mariupol, eastern Ukraine on November 29, 2018. (AFP PHOTO)

MOSCOW, Dec. 17 (Xinhua) -- Russia expects Ukraine to provoke it militarily on the border of Crimea in the last 10 days of December, Russian Foreign Minister Sergei Lavrov said Monday.

The Ukrainian Armed Forces have amassed around 12,000 troops and a great amount of equipment on the contact line with the insurgent region of Donbass, Lavrov told Russian newspaper Komsomolskaya Pravda.

Instructors from the United States, Britain and other countries are actively helping them, while a U.S. drone is constantly flying over the region, he said.

Ukraine introduced martial law in its Russian-speaking regions for 30 days, which is to expire on Dec. 26, following the seizure of three Ukrainian warships by Russia in the Black Sea due to their alleged breaching of Russia's border.

Ukrainian President Petro Poroshenko said at a press conference on Sunday that martial law will be lifted unless "a large-scale aggression, invasion by the Russian troops" takes place.

Poroshenko said that in the last 30 days Russia had amassed 300 tanks 18 km on the Ukrainian border, 80,000 servicemen and numerous artillery pieces in addition to a sharp increase in military presence in the Sea of Azov.

Crimea was incorporated into Russia in March 2014 following a local referendum, which neither Kiev nor Western countries recognize.