Palestinian President Mahmoud Abbas has announced a three-day mourning  after Israeli soldiers shot dead dozens of Palestinians on the Gaza border, EuroNews reported.

He went on to lash out at the US after it moved its embassy to contested Jerusalem on Monday, saying he "will not accept" any peace deal proposed by the Trump administration.

"This is not an embassy, it's a US settlement outpost, before that, we had an Israeli settlement outpost with the American support but now we have an American settlement outpost in East Jerusalem," he said.