The rebel Free Syrian Army said on Friday that Syrian troops were massing near the Turkish border amid tensions since Syria's downing of a Turkish jet last week.

"There are military units massing 15 kilometres or slightly more (10 miles), from the Turkish border, in the northern region" of Syria, FSA supreme military council head Mustafa al-Sheikh told AFP by telephone.

Asked to comment, a Syrian foreign ministry spokesman reported: "No hostile intentions from the Syrian side."

Sheikh said that around 2,500 troops backed by 170 tanks and other vehicles were stationed in the border area, roughly 25 kilometres (15 miles) from the main northern city of Aleppo, citing estimates from fighters on the ground.

Government forces have "regrouped and withdrawn from some of their checkpoints on the outskirts of Aleppo city to new locations" near the border, he said.

Sheikh said the troop build-up could be a "show of force against the Turkish military, which increased its presence on the Syrian border after the downing of its warplane by Syria."

"Fearing Turkish military intervention, the Syrian military proceeded to mobilise its forces," he said.

But he said the troop concentration might equally be in preparation for an operation inside Syria following heavy bombardment of the area by government forces in recent weeks.

"Another possibility for this mobilisation may be a crackdown in the northern Aleppo countryside," he said.

Turkey has sent missile batteries, tanks and troops to the border as a "security corridor" after Syria shot down a Turkish warplane late last week, media reports said.

State-run TRT television showed dozens of military vehicles reportedly heading for the border, in a convoy that included air defence systems.

The Turkish Phantom F-4 jet was downed by Syria over the eastern Mediterranean in what Prime Minister Recep Tayyip Erdogan called a "heinous attack" over international waters.

Turkey to pick new missile defence system soon
Istanbul (AFP) June 29, 2012 - Turkey is to pick a new long-range air defence missile system soon, as tension builds with neighbouring Syria, media and foreign diplomats said Friday.

Companies vying for the four billion dollar (3.2 billion euro) contract include Raytheon and Lockheed Martin of the United States, Rosoboronexport of Russia, CPMIEC of China and the French-Italian consortium, Eurosam, they said.

A Western diplomatic source said a shortlist would be announced on July 11 or 12.

The news comes a week after Syria shot down a Turkish warplane, prompting Turkey to start beefing up its forces along their lengthy border with anti-aircraft guns, missile batteries and tanks.

The Western diplomat said France had a better chance of winning the order following Francois Hollande's May election in succession to Nicolas Sarkozy, who upset Turkey with plans to make denial of the Armenian genocide a criminal offence.

China and Russia are unlikely to secure the contract for Turkey, a NATO member, since they are not part of the alliance, Hurriyet Daily News reported.

Turkey also hosts a NATO early warning radar as part of a new defence system aimed at protecting Europe from missiles coming from the Middle East, notably Iran.