YEREVAN: Russia said Saturday it would provide "necessary" assistance to Yerevan in its conflict with Azerbaijan if fighting reached Armenian territory after its ally requested help.

Armenian Prime Minister Nikol Pashinyan formally asked Russian President Vladimir Putin to begin "urgent" consultations on security assistance in its conflict with Azerbaijan over the breakaway region of Nagorno-Karabakh.

Armenia and Azerbaijan have been engaged in fierce fighting for more than a month over Karabakh, a region of Azerbaijan controlled by Armenian separatists in the wake of the break-up of the Soviet Union.

Azerbaijani forces have recently been making gains against Armenian separatist fighters and world powers have so far been unable to persuade the warring sides to halt fire. The flare-up has left more than a thousand dead.

Pasninyan requested assistance from Moscow after Armenia and Azerbaijan failed to agree a fresh ceasefire during talks in Geneva on Friday, and fighting continued overnight and Saturday.

The announcement raised fears of Russia and Baku's ally Turkey of getting sucked into the decades-old conflict. Russia has a military base in Armenia's second-largest city of Gyumri and a defence treaty with Yerevan. Moscow's defence pact with Armenia does not however, extend to Nagorno-Karabakh, and Russia said Saturday help would only be provided if the fighting reaches Armenian territory.

"Russia will render Yerevan all necessary assistance if clashes take place directly on the territory of Armenia," the foreign ministry said. At the same time, foreign ministry spokeswoman Maria Zakharova said "concrete formats" of assistance to Armenia would be discussed.