Syrian regime backers Russia and Iran and opposition supporter Turkey on Thursday (May 4th) signed a pact to create safe zones in Syria meant to halt fighting in the country, AFP reported.

Several members of the opposition delegation, however, left the room shouting as the signing took place at talks in the Kazakh capital Astana, angry at regime ally Iran.

The Syrian government and opposition delegations are not signatories to the agreement, which was signed by the talks' three sponsors.

Turkey's foreign ministry said the zones would cover the whole of Idlib province, portions of the Latakia, Aleppo, Hama and Homs provinces, as well as the Ghouta suburb of Damascus.

The zones will also include parts of the Daraa and Quneitra provinces, the ministry said.

The zones were set to remain in place for six months, a period that could eventually be extended. The deal also foresees a halt in fighting in the zones.

The Turkish foreign ministry said the zones' parameters would be determined shortly by a working group formed by the talks' three sponsors.

"We welcome with satisfaction this memorandum, which foresees a halt in the use of all categories of arms among belligerents, including aerial weapons, as well as the rapid and uninterrupted influx of humanitarian aid toward those zones," the ministry said in a statement.

The aim of the zones is to "put an immediate end to the violence" and "provide the conditions for the safe, voluntary return of refugees" as well as the immediate delivery of relief supplies and medical aid, the document said.

But issues including which countries could police any safe zones remained unclear.

The Syrian opposition said earlier Thursday that they had resumed participation in the talks after having suspended their involvement a day earlier over airstrikes against civilians.