President Tayyip Erdogan claimed victory in Turkey’s presidential election on Sunday, a win that would steer his increasingly authoritarian rule into a third decade after he saw off his toughest political challenge yet.

Addressing supporters from on top of a bus in Istanbul, Erdogan thanked people for voting and said Turks had given him the responsibility of governing for the next five years.

“The only winner is Turkey,” he said.

Final official results have yet to be released.