U.S. Secretary of State Rex Tillerson says a meeting between President Donald Trump and Russian President Vladimir Putin is “still under consideration.”

Tillerson says the two sides never agreed to hold a formal one-on-one meeting during a summit of southeast Asian nations this week in Vietnam.

He says a deciding factor is whether they have “sufficient substance” to talk about.

Trump repeated Thursday after meetings in Beijing with China’s president that he also wants Russia’s help getting North Korea to give up its nuclear weapons.

Tillerson briefed U.S. reporters after Trump’s meetings. He suggested that the leaders need something “useful” to point to in order to meet.

Trump and Putin met earlier this year during a conference in Germany.

(AP)