US Secretary of State Marco Rubio has said "a lot of countries" have offered to be part of an international security force for Gaza - a key part of President Donald Trump's peace plan - but added Israel would have to be comfortable with participants.
Speaking on a visit to Israel, Rubio said talks on forming the International Stabilization Force (ISF) were continuing and that it would come into effect "as soon as it possibly can".
It remained unclear, however, how such a force could be deployed without an understanding with Hamas.
He said the Israel-Hamas ceasefire had made "historic" progress since it began two weeks ago, but warned to expect "ups and downs and twists and turns".
"There is no plan B," he said. "This is the best plan. It's the only plan. And it's one that we think can succeed."
