The president of Finland Alejandro Stubb said a call he had with donald trump Monday night made it clear that the president-elect needs to be taken seriously when he talks about ending Russia’s war in Ukraine.

“We in Europe and the rest of the world must understand that Donald Trump is very serious about reaching a peace agreement as soon as possible,” Stubb said in an interview on Bloomberg TV on Tuesday. “There is a window of opportunity for these negotiations between the election and Inauguration Day.”