NATO foreign ministers are expected on Tuesday to approve Turkey's request for Patriot missiles to defend the country from potential attack from neighboring Syria, NATO Secretary General Anders Fogh Rasmussen said.

"I would expect NATO allies to make a decision later today. I am confident we will demonstrate our determination to deter any threats and defend our ally," he said just ahead of the two-day gathering of foreign ministers from 28 NATO members.

The NATO chief repeated that any deployment of the Patriots in Turkey would be "defensive only" and would in no way support a no-fly zone or any offensive operation.