Burhan Ozbilici, Associated Press
Russian President Vladimir Putin speaks to the media during a joint news conference with his Turkish counterpart Recep Tayyip Erdogan at the new Presidential Palace in Ankara, Turkey, Monday, Dec. 1, 2014. Russia is scrapping the South Stream natural gas pipeline project and may cooperate with Turkey on building a gas hub for southern Europe, President Vladimir Putin said Monday.

ANKARA, Turkey — Russia is scrapping the South Stream natural gas pipeline project and may cooperate with Turkey on building a gas hub for southern Europe, President Vladimir Putin said Monday.

He said Russia can't implement the South Stream project because of the European Union's opposition to it. The project would have involved running a pipeline under the Black Sea to Bulgaria and further on to southern Europe.

However, Moscow will boost gas supplies to Turkey and may cooperate with it in creating a hub for natural gas supplies on the border with Greece, he said.

Putin met his Turkish counterpart Recep Tayyip Erdogan amid striking differences over the crises in Syria and Ukraine, but the leaders focused instead on their countries' booming economic and trade ties. The Russian leader arrived in Turkey accompanied by a large delegation, including 10 ministers.

The two countries, who are major trading partners, have set an aim of increasing their two-way trade volume from $33 billion to $100 billion by 2020.

Russia provides the bulk of Turkey's gas and is set to build Turkey's first nuclear power plant. Turkish construction firms are active in Russia while millions of Russian tourists travel to Turkey each year.

The Russian and Turkish leaders, often compared to each other for their drift toward authoritarianism, have opposing positions on Syria's crisis, but were expected to set their differences aside. Russia remains Syrian leader Bashar Assad's closest ally, while Turkey supports Syria's opposition forces.

Erdogan makes no secret of his desire to see Assad deposed.

Turkey has also been a strong advocate of the Tatar community in the Russia-annexed Crimean Peninsula and has publicly supported Ukraine's territorial integrity. Barred by Russian authorities from Crimea, Tatar leaders who strongly opposed the annexation are feted in Turkey. On a visit just a month after the annexation, Tatar Soviet-era dissident Mustafa Dzhemilev was given Turkey's highest award.

"Turkey and Russia don't share the same views on many issues, in particular on Syria ... (but) Turkey will continue to purchase energy from Russia," said Professor Huseyin Bagci of Ankara's Middle East Technical University. "They will put Syria to one side during their discussions."

Putin was welcomed at Erdogan's new mega-palace, which has drawn the ire of Turkish opposition parties, environmentalists and activists who say the 1,000-room complex is too costly and extravagant and went ahead despite a court ruling. Putin is the second foreign dignitary to receive an official welcome at the palace, after Pope Francis who visited on Friday.

On Monday, a Crimean Tatars' solidarity group staged a protest at a park near Turkey's parliament in Ankara to protest Putin's visit. About 50 children from the Caucasus region, including from Chechnya, also demonstrated in Istanbul, the state-run Anadolu Agency reported.

Nataliya Vasilyeva and Vladimir Isachenkov in Moscow contributed to this report.