President Donald Trump will not have a formal meeting with Russian President Vladimir Putin while the two are in Danang, Vietman, for a summit.

White House press secretary Sarah Huckabee Sanders is blaming a scheduling conflict for the fact that the leaders will not meet at the Asia-Pacific Economic Cooperation summit.

Sanders told reporters traveling with Trump in Asia that it’s still possible the two could have a less formal encounter on the sidelines of the summit in Vietnam or a later gathering in the Philippines.

US Secretary of State Rex Tillerson told reporters in Beijing on Thursday that there was no reason for the leaders to meet if they weren’t able to make significant progress on issues including Syria and Ukraine.