ANKARA: Turkey on Sunday vowed complete support for Baku and called on Armenia to give up its "aggression" after heavy fighting erupted in Azerbaijan's breakaway region of Nagorny Karabakh.

"We will support our Azerbaijani brothers with all our means in their fight to protect their territorial integrity," Turkish Defence Minister Hulusi Akar said in a statement.

The worst clashes since 2016 broke out on Sunday between arch-foes Azerbaijan and Armenia who have been locked for decades in a territorial dispute over Nagorny Karabakh.

Turkey is a key ally of Baku with close cultural and linguistic ties with Azerbaijan.

Ankara has no diplomatic relations with Yerevan due to a dispute over the mass killings of Armenians in the Ottoman Empire which Armenia says is a genocide.

"The greatest obstacle to peace and stability in the Caucasus is Armenia's aggression, and it should give up this aggression which will throw the region into fire," Akar said.

Turkish presidential spokesman Ibrahim Kalin "strongly" condemned the clashes and said Armenia "once again violated international law and (has) shown that it has no interest in peace and stability."

He called on the international community to "say stop to this dangerous provocation" in a tweet.

"Azerbaijan is not alone. It has Turkey's full support," Kalin added.The Turkish foreign ministry in a statement went further, promising: "However Azerbaijan wants, we will stand by Azerbaijan in that manner."

Turkish Foreign Minister Mevlut Cavusoglu and Russian counterpart Sergei Lavrov discussed the crisis on Sunday during a telephone conversation, a Turkish diplomatic source said, without giving details.