MOSCOW — Russian Foreign Minister Sergei Lavrov said on Wednesday the West had to drop its demands about the political exit of Syrian President Bashar al-Assad if it wanted a genuinely international coalition against ISIS.

Lavrov, who said there was still no agreement about Assad’s political fate after international talks in Vienna, said he had detected a change in the West’s position since the Paris attacks and the bombing of a Russian passenger plane.

Russia, which views Syria as its closest Middle East ally, has long been at odds with the West over Assad’s future with Moscow saying only the Syrian people should decide if he steps down. The United States and others want Assad to step aside during or at the end of a transition period.

“I hope the change in the position of our Western colleagues, which has unfortunately only come about as the result of terrible acts of terror, will spread to other Western partners. That the stance that the real battle with ISIS can only be resolved once the fate of Assad is clear, that this position will put to one side,” said Lavrov.

“In my opinion there can now be no doubts that it is simply unacceptable to put forward any preconditions in order to unite in the battle against so-called ‘Islamic State’ terrorists.”

However, President Obama reiterated the U.S. stand on Thursday, saying that Assad must go.

“I do not foresee a situation in which we can end the civil war in Syria while Assad remains in power,” Obama said.