Chinese State Councilor Yang Jiechi told the European Union's (EU) top diplomat, Catherine Ashton, Wednesday that China-EU ties were his country's top priority in foreign policy.

Speaking to the EU High Representative for Foreign Affairs and Security Policy by phone, Yang said the two sides should focus on cooperation and a win-win spirit, and push forward the China-EU comprehensive strategic partnership.

Ashton said the EU expected to maintain all forms of dialogue and exchange mechanisms with the Chinese side, and expand cooperation to make the EU-China ties more fruitful.

The two sides agreed to be well prepared for the 16th summit meeting of the EU and Chinese leaders this year.

They also exchanged views on Iran's nuclear program. Yang hoped the relevant parties could make joint efforts to continue dialogue and deal with the issue through diplomatic negotiations.