Syria has condemned Turkey's request for NATO to deploy Patriot defence missiles near their common border, lebelling it "provocative".

A spate of fighting in the area has raised fears of the Syrian civil war embroiling the wider region.

In the first Syrian response to Ankara's request earlier this week, a ministry source told Syrian state television that Damascus would hold Turkey's prime minister responsible for increasing tensions along the frontier.

The 20-month-old uprising against Syrian President Bashar al-Assad has grown increasingly bloody and heavy clashes often erupt right along Syria's northern border with Turkey.

Ankara has repeatedly scrambled fighter jets and responded in kind to stray shells flying into its territory.

Turkey's missile request may have riled Damascus and its allies because it could be seen as a first step toward implementing a no-fly zone.

Syrian rebels have been requesting one to help them hold territory against a government with overwhelming firepower from the air, but which most foreign governments are loath to impose for fear of getting sucked into the conflict.

The Patriot system is designed to intercept aircraft or missiles. Turkey asked for its deployment after weeks of talks with its NATO allies about how to shore up its 900km border, where it fears security may deteriorate as the Syrian army steps up fighting against rebel advances.

"Syria stresses its condemnation of the Turkish government's latest provocative step," the ministry source told Syria TV.

The source said that Syria would respect Turkish sovereignty but also said that it "holds (Tayyip) Erdogan responsible for the militarisation of the situation on the Syrian-Turkish border and increased tensions".

NATO chief Anders Fogh Rasmussen said yesterday that the possible deployment of Patriot missiles was "purely defensive" and would "serve as a deterrent to possible enemies even thinking of attacks".

The US-led Western alliance has had some talks on the Turkish request but no decision is expected before next week.

Rebels capture army base in Syria

Syrian rebels have captured an army base in an eastern oil province, further weakening President Assad's control in the strategic region bordering Iraq.

The capture of the artillery base on the outskirts of Mayadeen, near some of Syria's main oilfields, followed earlier rebel takeovers of military installations in the north and centre of the country.

Video posted online showed rebels on motorcycles and trucks apparently inside the base waving victory signs as smoke rose from two buildings.

Artillery pieces could be seen on the ground and a tank transporter stood abandoned.

Severe restrictions on non-state media make it difficult to verify opposition reports independently.

Activists say 40,000 people have been killed in the 20-month uprising, which threatens to draw in regional Sunni and Shia Muslim powers.

Rami Abdelrahman, head of the Syrian Observatory for Human Rights, said about half the fatalities were civilians and the other half split about evenly between rebels and government soldiers.

"The figure is likely much higher as the rebels and the government lie about how many of their forces have died to make it look like they are winning," said Mr Abdelrahman.

Hundreds of thousands have fled the country and 2.5 million are displaced, aid groups say.

The capture of the Mayadeen base leaves Mr Assad in control of just three major army bases in Deir al-Zor province, a local tribal leader said.

He also said rebels now held the main road to Iraq, from the outskirts of Deir al-Zor city to the border crossing of Albu Kamal.

Near Damascus, opposition campaigners said fighting continued around the southwestern suburb of Daraya and the army kept up heavy bombardment of the town, where Free Syrian Army fighters appeared to be entrenched.