Donald Trump’s administration has rebuffed efforts by Middle Eastern allies to start diplomatic negotiations aimed at ending the Iran war that started two weeks ago ​with a massive U.S.-Israeli air assault, according to three sources familiar with the efforts.

Iran, for its part, has rejected the possibility of any ceasefire until U.S. and Israeli ‌strikes end, two senior Iranian sources told Reuters, adding that several countries had been trying to mediate an end to the conflict.

The lack of interest from Washington and Tehran suggests both sides are digging in for an extended conflict, even as the widening war inflicts civilian casualties and Iran’s closure of the Strait of Hormuz sends oil prices soaring.