UNITED NATIONS - Syria on Thursday formally applied to join the Organization for the Prohibition of Chemical Weapons (OPCW), vowing to immediately fully abide with the treaty.

Bashar Ja'afari, the Syrian ambassador to the United Nations, tied the move to an earlier Damascus bid for a Middle East zone free of weapons of mass destruction (WMD), including an end to Israel's alleged nuclear armaments.

A spokesman for UN Secretary-General Ban Ki-moon said in a statement that the secretary-general received a letter from Damascus "informing him that President (Bashar) Al-Assad has signed the legislative decree providing for the accession of Syria to the Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on their Destruction."

"In their letter, the Syrian authorities have expressed their commitment to observing the obligations entailed by the Convention even before its entry into force for Syria," the statement said.

"The Secretary-General welcomes this development, noting that, as depository of the Convention, he has long called for universal accession to the Chemical Weapons Convention."

The spokesman added: "Given recent events, he (Ban) hopes that the current talks in Geneva will lead to speedy agreement on a way forward which will be endorsed and assisted by the international community."

Earlier in the day, Farhan Haq, associate UN spokesman, said that Lakhdar Brahimi, the joint Arab League-United Nations envoy, had met with US Secretary of State John Kerry and was to meet with Russian Foreign Minister Sergey Lavrov. Kerry and Lavrov kicked off talks on Syria late Thursday in Geneva.

Meanwhile, Syria's UN ambassador Ja'afari met with reporters at UN Headquarters Thursday afternoon, claiming Damascus never denied possessing any WMD.

"We always said while talking about chemical weapons, if they exist," he said. "The chemical weapons in Syria are a mere deterrence against the Israeli nuclear arsenal. It's a deterrence."

He said the Syrian government's application to join the OPCW showed its willingness to oppose WMD, proving its desire for the "establishment in the Middle East of a zone free of all WMD."

"In the foremost, and the forefront of it, the Israeli nuclear armaments should be dismantled ... and so the area would be free of all WMD. So we joined the deeds to the words today," he added.

The Damascus envoy said there were "no preconditions" for joining the OPCW convention, noting Syria's decision to join the convention is "nothing new".

The ambassador urged media not to speculate on the upcoming UN investigation report on the alleged chemical weapon attack on August 21 in Ghouta, Syria.

"I would like to urge all of you, professional journalists and reporters, to be on the positive side of what is being reported," Ja'afari said.

"The media might be a WMD too. So please let us be responsible. Let us act with this very important decision by the Syrian government, positively speaking. We don't need any anticipation. We don't need if. We need just to judge things as they are produced by the Syrian government as well as by the Russians and by the Americans and the secretary-general."

Earlier reports said the UN report could be released later this week, while recent speculation points to next week.