Spain's main opposition party said Tuesday that Turkish-EU relations should be based on mutual trust.

President of the right-wing People's Party (PP) Alberto Nunez Feijoo argued that Ankara's position on the war in Ukraine would be decisive for the future of its relations with the bloc.

"The war made the relations of the bloc with Türkiye even more complicated," he told foreign reporters, including a reporter from Anadolu Agency (AA).

He highlighted that Türkiye is an important country with its economy, population and geostrategic location.

"I think, presently, the relations are passing through critical times," he said, noting that Ankara should decide whether it will be in line with the bloc's policies toward Russia.

Since the beginning of the war in Ukraine on Feb. 24, Ankara has been firm on finding a peaceful solution to end hostilities and bring about a permanent resolution while supporting Ukraine's territorial integrity loudly.

President Recep Tayyip Erdoğan and senior Turkish officials have repeatedly said Ankara is ready to contribute to ending the war through diplomacy and invited both leaders to meet in Türkiye.

Türkiye, the United Nations, Russia and Ukraine signed a deal in Istanbul on July 22 to reopen three Ukrainian Black Sea ports to export Ukrainian grain stuck due to the war, which is now in its eighth month.

Türkiye played an instrumental role in a deal in late September that led to Moscow releasing 215 Ukrainian soldiers in exchange for 55 Russian servicemen.

Hailed in Ukraine as the "defenders of Azovstal," the five Ukrainians are in Türkiye under personal guarantees of protection by Erdoğan, according to a statement from the Ukrainian presidential office.

Türkiye expects the European Union to handle its enlargement policy more seriously and act more encouragingly towards candidate countries, Deputy Foreign Minister and Director for EU Affairs Faruk Kaymakcı recently told Daily Sabah, adding that Russia's war on Ukraine has increased the need for enlargement in both the EU and NATO.

Türkiye-EU relations are marked by disputes on several issues, including tensions in the Eastern Mediterranean, Türkiye's role in Syria, the migrant crisis and the stalemate in Türkiye's accession process to join the bloc. However, Türkiye has recently reiterated that it is part of Europe and sees its future in the EU, adding that it will continue to work toward full membership. Ankara is calling to reenergize the accession process and update the Türkiye-EU Customs Union as it advocates for regular high-level dialogues, visa liberalization and further counterterrorism efforts.

Türkiye has the longest history with the union and the longest negotiation process. The country signed an association agreement with the EU's predecessor in 1964, the European Economic Community (EEC), which is usually regarded as a first step to eventually becoming a candidate. Applying for official candidacy in 1987, Türkiye had to wait until 1999 to be granted the status of a candidate country. For the start of the negotiations, however, Türkiye had to wait for another six years, until 2005, a uniquely long process compared with other candidates. In recent years, the accession process seems stalled.