Turkish President Recep Tayyip Erdogan pledged gas, investment and support for the Balkans on Tuesday. His two-day trip to Serbia — a mainly Orthodox Christian country at fierce odds with Turkey during Yugoslavia’s bloody collapse — could help grow Turkey’s role in a region that spent centuries under Ottoman rule and remains susceptible to big-power rivalries.

Turkish influence is already strong among fellow Muslims in Bosnia, Albania and Kosovo. Serbia is Russia’s closest ally in the Balkans.

“Together with Serbia and with the entire Balkans, we want to make steps to resolve all the problems,” Erdogan told reporters in Belgrade, saying Ankara planned to build a road between Serbia and Bosnia.

Erdogan and his Serbian counterpart, Aleksandar Vucic, signed a political declaration to create a cooperation body that would meet annually to coordinate joint projects.

Erdogan expressed confidence that Russia would not object to a Turkish plan to transfer natural gas from its TurkStream project to Serbia.

“We do not want any division of the Balkans or that someone might see those countries as their sphere of influence. We oppose all those who want that,” Erdogan told a business forum.

The visit, and Erdogan’s thanks to Vucic for his support during a failed coup in 2016, will not go unnoticed in the European Union, where some diplomats are concerned about deepening authoritarianism among some Balkan leaders in the absence of tangible progress towards EU accession.