Shtayyeh spoke to his Cabinet as Israeli Prime Minister Benjamin Netanyahu was visiting Washington for the announcement of US President Donald Trump's plan to resolve the Israeli-Palestinian conflict.
Shtayyeh said the plan violates international law and "comes from a party that has lost its credibility to be an honest broker in a serious and genuine political process”, AP reported.
The Palestinians have not yet seen the plan but have already rejected it, saying the Trump administration is biased in support of the Israelis.
Reports in Israeli media have speculated the plan will be extremely favorable to Israel, including the possible annexation of large pieces of Palestinian territory.
A Palestinian official said that President Mahmoud Abbas has rejected overtures from mediators in recent weeks to arrange a phone call with Trump. The official spoke on condition of anonymity because he was discussing a classified diplomatic issue.
Trump and Netanyahu are slated to meet Tuesday to discuss the much-vaunted “Deal of the Century". The White House invited the Israeli prime minister and his main opponent, Blue and White party leader Benny Gantz, to Washington on Monday to announce the plan just weeks before Israel's third parliamentary election in under a year.