A senior US defence official has held talks in Turkey, the embassy said Saturday, after Washington expressed "serious concerns" about Ankara's plans to acquire a long-range anti-missile system from China.

Turkey announced in September it was entering negotiations with the China Precision Machinery Export-Import Corporation (CPMIEC) to buy its first long-range anti-missile system.

The move irritated its NATO allies, particularly the United States, which has imposed sanctions on CPMIEC for selling arms and missile technology to Iran and Syria.

"Under Secretary of Defence for Policy Jim Miller visited Turkey for bilateral consultations on regional security issues, including Syria, the US-Turkish bilateral defence relationship, and our partnership in NATO," US embassy spokesman T.J. Grubisha told AFP.

US Ambassador to Turkey Francis Ricciardone said last month that Washington was concerned about the prospect of a deal with the Chinese company.

"There's no disagreement between us but we are seriously concerned about what this means for allied missile air defence," he said.

NATO chief Anders Fogh Rasmussen has also voiced concern about the decision and said missile systems within the transatlantic military alliance must be compatible with each other.

CPMIEC, which makes the HQ-9 missile system, beat competition from a US partnership of Raytheon and Lockheed Martin, Russia's Rosoboronexport, and Italian-French consortium Eurosam for the deal, estimated at $4 billion (2.9 billion euros).

Turkey has defended its decision to enter into talks with the Chinese company but said it is open to new bids should the negotiations fall through.

US Assistant Secretary of State for European and Eurasian Affairs Victoria Nuland will hold talks in Istanbul and in the southern city of Adana next week, the embassy spokesman said.

Turkey's foreign minister will travel to Washington on November 18, but will not discuss the missile deal unless the US side brings it up, a Turkish diplomatic source told AFP.