Assad believes such a meeting would help Erdogan in Turkey's June elections, allowing him to signal progress on returning some of the 3.6 million Syrian refugees living in Turkey to its neighbor, according to Reuters.

"Why hand Erdogan a victory for free? No rapprochement will happen before the elections," an unnamed source with knowledge of Syria's thinking told Reuters.

The feud between Assad and Erdogan goes back to the Arab Spring when Turkey funded militant groups opposed to Damascus.

Last month Erdogan said he was open to resetting relations with Syria.

"There can be no resentment in politics," he said in a television interview over the weekend.

Turkey and Syria's intelligence chiefs have held multiple meetings in Damascus this year with the aim of arranging a potential meeting between the two countries' foreign ministers, but one of the sources quoted by Reuters said Damascus had turned down the meeting.

A source with knowledge of Turkey’s thinking told Reuters an Assad-Erdogan meeting could still be possible "in the not too distant future".

"Putin is slowly preparing the path for this," the source said. "It would be the beginning of a major change in Syria and would have very positive effects on Turkey. Russia would benefit too... given it is stretched in many areas."

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