Hamas on Monday announced it would stop releasing Israeli hostages until further notice over what the Palestinian militant group called Israeli violations of a ceasefire agreement in Gaza, raising the risk of reigniting the conflict.

Trump’s proposal to relocate Palestinians out of Gaza and take over the territory was rejected by several foreign nations, including Saudi Arabia, Turkey and China.

A spokesperson for the armed wing of Hamas says the group is postponing the next scheduled release of Israeli hostages, blaming what he said were Israeli violations of the ceasefire deal. Three hostages held in Gaza are due to be freed on Saturday in exchange for more Palestinian prisoners held in Israel.