Brussels - Turkey has proven itself to be a reliable international partner and a key energy transit route, but it must work harder on political and human-rights reforms if it wants to join the European Union, the EU's executive said Wednesday.

"Despite its strong political mandate, the government did not put forward a consistent and comprehensive programme of political reforms" which would have brought Turkey closer to EU norms, the European Commission said in its annual report on would-be EU member states.

Turkey has been a candidate for EU membership since 1999 and opened formal talks on accession in 2005, but officials in Brussels say that its progress has been limited, especially under the impact of the summer's power struggle between the ruling AKP party and the country's secularist elite.

"The lack of dialogue and spirit of compromise between the main political parties had a negative impact on the smooth functioning of the political institutions ... Concerns remain about the independence and impartiality of the judiciary," the commission report said.

Turkey's perceived weakness in fighting organized crime is also a "serious concern," the paper said.

And its policy of vetoing the entry of EU member Cyprus into international organizations, and its refusal to let NATO, of which it is a member, cooperate fully with the EU because of its dispute with Cyprus, "created problems for EU-NATO co-operation."

"Turkey needs to take concrete steps to contribute to a favourable climate for a comprehensive settlement" on Cyprus, the paper said.

However, the commission paper also praised Turkey's cooperation on foreign-policy issues such as Iraq, Iran and the summer's Russian- Georgian war.

"Turkey has enhanced its positive role of regional stabilization, in particular as regards the Caucasus and the Middle East ... Turkey is contributing substantially to (EU security missions) and seeking greater involvement in (such) activities," it said.

And it acknowledged Turkey's importance as a transit country for natural gas, stressing that "the Turkish authorities have repeatedly confirmed their commitment to the realization of the (Nabucco) project" for bringing Azeri gas to the EU, bypassing Russia.

EU Energy Commissioner Andris Piebalgs is set to travel to Ankara later Wednesday to discuss the Nabucco project amidst concerns over Turkey's policy of transit fees. (dpa)