Reports: Turkey sent Syrian fighters to Azerbaijan

At least 500 Syrian fighters had already gone to Azerbaijan before them, the SNA and the Syrian Observatory for Human Rights, an NGO, also told British newspaper The Guardian.

A Turkish private security firm was paying them $1,500 a month, moving them across the border into Turkey, then flying them to Azerbaijan, Syrian sources said.

The reports came out after Armenia's ambassador to Russia, Vardan Toganyan, said on Monday there were 4,000 Syrian fighters in Azerbaijan, as well as Turkish military advisors, and weapons systems.

He spoke amid a second day of warfare over the Armenia-controlled Nagorno-Karabakh region in Azerbaijan, which erupted on Sunday and which has claimed dozens of lives on both sides.

The Armenian ambassador threatened to invoke a defence pact with Russia under the Collective Security Treaty Organisation.

"We believe that should the need arise, we will request Russia [for additional military assistance] ... As of today, we don't think that we need additional troops or other forces," Toganyan said.

And fears that neighbouring states were getting drawn into the 30-year old ethnic conflict saw the value of the Turkish lira drop on Monday.

Azerbaijani and Turkish officials have denied using Syrian mercenaries.

"It was complete nonsense," Hikmat Hajiyev, a foreign policy aide to Azerbaijani president Ilham Alyiev, told Reuters.

"Our [own] armed forces have more than enough personnel and reserve forces," he said.

But Turkish president Recep Tayyip Erdoğan claimed the right to intervene on Azerbaijan's side in a speech in Istanbul on Monday.

France, Russia, and the US, which led international diplomacy on the conflict, had "done nothing" to solve it in 30 years Erdoğan said.

"Now they give advice and sometimes threaten. What is this threat? 'Is Turkey here? Are there any Turkish soldiers here [they ask]?'," Erdoğan said.

Azerbaijan "had to take matters into its own hands" and Turkey would "stand with ... Azerbaijan with all its resources and heart," he added.

"It is time to end the crisis ... The region will once again see peace after Armenia immediately withdraws from the Azeri lands it is occupying," Erdoğan said.

His aggressive posture on Nagorno-Karabakh comes after Turkey sent forces to Libya and Syria in the past year and harassed Cyprus and Greece with oil and gas drilling in their waters.

The EU foreign service said on Monday it had no hard facts on Syrian fighters in Azerbaijan.

But "foreign interference was not acceptable", it added.

EU leaders are to discuss Turkey relations at a special summit on Thursday and Friday, amid calls by Cyprus to impose sanctions.

Erdoğan accused them of a "colonialist mentality" and "imperialist expansionism" in the eastern Mediterranean in his Istanbul speech, auguring badly for an amicable solution.

"Ottoman peace has now been replaced by a brutal order in which humanity is shelved for oil, natural gas, and profit," the Turkish president said.

Olive branch?

But he also spoke of "diplomatic efforts" with German chancellor Angela Merkel, which gave him hope of a "win-win-based formula that protects everyone's rights" in sharing gas resources.

"Let's all turn the Mediterranean into a peace basin," Erdoğan said.

He spoke the same day to British prime minister Boris Johnson, whose office "welcomed the news that Turkey and Greece have agreed to talks".

And Erdoğan's spokesman, Ibrahim Kalin, also held out an olive branch.

"I believe the EU summit has a chance to have a reset in Turkey-EU relations. It is an important opportunity ... and I see this willingness on the part of many EU member countries," Kalin told Reuters on Monday.