The Palestinian Foreign Ministry said Sunday it was considering filing a complaint against US Ambassador to Israel, David Friedman, at the International Criminal Court (ICC).
The move came after Friedman said Saturday that Israel has the right to annex parts of the occupied West Bank.
In a statement, the ministry said Friedman's statements "give proof that he was a threat to peace and security in the region".
The ministry said the envoy's words were "an extension of the policy of the US administration, which is fully biased towards the occupation and its expansionist colonial policies".
"What reasoning could justify Friedman's logic that Israel has the right to annex parts of the West Bank?" the ministry asked, adding:
International law prohibits the annexation of a land by force, as well as a reality imposed by occupying powers.
In an interview with The New York Times, Friedman, a staunch supporter of Israeli settlement building, declined to say how Washington would respond if Israel moved to annex West Bank land unilaterally. In the interview, Friedman said:
Under certain circumstances, I think Israel has the right to retain some, but unlikely all, of the West Bank.
The Palestinian leadership has refused to deal with the Trump administration since it recognised Jerusalem as Israel's capital. Palestinians want the eastern part of the city, captured by Israel in the 1967 war and annexed in a move unrecognised abroad, as their future capital.
In March, Trump recognised Israeli sovereignty over the Golan Heights, territory that Israel captured from Syria in the same war and later annexed.
Netanyahu told Army Radio in April that Trump's Golan step showed it was possible to annex West Bank settlements "within a gradual process and I prefer to do so with American recognition".
He added: "I have been discussing the question of extending sovereignty with the Americans for the past six months."
Read: Netanyahu reaffirms West Bank annexation, despite ex-security officials' petition