President Donald Trump will draw a red line on how long to give Hamas to accept an Israel-backed proposal to halt fighting in Gaza, the White House said on Thursday, without explicitly saying whether he would enforce a previously set deadline.

Trump on Tuesday said he would give Hamas three to four days to accept the 20-point document, which calls on the militant group to disarm – a demand it has previously rejected. Hamas is reviewing the proposal, a source close to the group said on Wednesday.

Asked to identify a point at which Hamas would be considered to have "walked away" from the proposal, White House spokeswoman Karoline Leavitt said:

"Well, it's a very good question, and it's a red line that the president of the United States is going to have to draw. And I'm confident that he will. But the president and his team worked very hard on this 20-point, comprehensive, detailed plan that has been applauded all over the world."

"This is an acceptable plan, and we hope and we expect Hamas should accept this plan so we can move forward," Leavitt added.

The plan specifies an immediate ceasefire, an exchange of all hostages held by Hamas for Palestinian prisoners held by Israel, a staged Israeli withdrawal from Gaza, the disarmament of Hamas and the introduction of a transitional government led by an international body.

Many elements of the 20 points have been included in numerous ceasefire deals proposed over the last two years, including those accepted and then subsequently rejected at various stages by both Israel and Hamas.