BRUSSELS (Reuters) - NATO said on Wednesday it would consider a Turkish request to deploy Patriot missiles on its territory to help it defend itself against any Syrian attacks.

Ankara's bid for the missiles followed talks with NATO allies about how to shore up security on the 900-km (560-mile) border with Syria after mortar rounds landed on Turkish territory, increasing concerns about the civil war spilling over into Syria's neighbors.

The head of NATO said the alliance would discuss the request "without delay", while ambassadors from the 28 NATO members convened a meeting at the alliance's Brussels headquarters.

"Such a deployment would augment Turkey's air defense capabilities to defend the population and territory of Turkey," Secretary-General Anders Fogh Rasmussen said.

"It would contribute to the de-escalation of the crisis along NATO's south-eastern border."

Rasmussen has said any missile deployment would be a defensive measure to counterattacks, and not to enforce a no-fly zone over Syria. Rebels fighting President Bashar al-Assad's forces have called for a no-fly zone as they are almost defenseless against Syria's air force.

Germany Foreign Minister Guido Westerwelle said on Wednesday he had told his ambassador to NATO to approve Turkey's request.

Germany, the Netherlands and the United States, are the only three NATO allies with appropriate systems available.

The Dutch government said it would consider the request.

NATO has deployed Patriot surface-to-air missiles to Turkey twice before, once in 1991 and again in 2003, during both Gulf Wars. Those missiles were provided by the Netherlands.

Ankara twice this year has invoked Article 4 of the NATO charter which provides for consultations when a member state feels that its territorial integrity, political independence or security is under threat.

But some experts said deploying Patriots to Turkey would be partly symbolic, aimed at showing that NATO was behind Turkey.

Manufacturer Raytheon says Patriot provides "a reliable and lethal capability to defeat advanced threats, including aircraft, tactical ballistic missiles, cruise missiles and UAVs (drones)".

(Reporting by Sebastian Moffett and Justyna Pawlak; Editing by Michael Roddy)