The leaders of Russia and Turkey met Monday amid striking differences over the crises in Syria and Ukraine, but the two presidents were expected to focus instead on their countries' booming economic and trade ties.

Russian President Vladimir Putin arrived in Turkey accompanied by a large delegation, including 10 ministers, for discussions officials say will concentrate on trade, including a Turkish demand for a price reduction on natural gas purchases from Russia.

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 are expected to set their differences aside. Russia remains Syrian leader Bashar Assad's closest ally, while Turkey supports Syria's opposition forces.

Turkish President Recep Tayyip 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.