LONDON (AFP) – Syrian President Bashar al-Assad could prevent a U.S.-led attack if he turned over his chemical weapons in the next week, Secretary of State John Kerry said on Monday.

But Kerry told a press conference in London that he had no expectation that Assad would give up the arms.

The top U.S. diplomat was asked if there was anything that the Syrian government could do or offer now to prevent a military strike.

“Sure, he could turn over every single bit of his chemical weapons to the international community in the next week — turn it over, all of it, without delay and allow a full and total accounting for that,” Kerry told reporters.

“But he isn’t about to do it and it can’t be done.”