Trump has promised to move the U.S. embassy during his electoral campaign, but he has since appeared to tone down his commitment to it.
Every president has signed a waiver every six months on a 1995 law calling for the embassy to be moved to Jerusalem. The latest waiver is expected to expire in May.
Speaking to reporters in Jerusalem late Sunday, Congressman Ron De Santis said he believes Trump might not sign the waiver when it ends.
"I don't think that he's going to, on the same month where people here in Jerusalem are celebrating the 50th anniversary of Jerusalem Day, sign the waiver,” said De Santis, who arrived in Israel late Saturday, leading an unofficial Congressional delegation to explore the potential of relocating the embassy.
“I would bet that he would not do that and he would announce that the embassy would be moving," he said.
Palestinians have opposed the move, arguing it would mean recognizing Jerusalem as Israel's capital despite the city’s disputed status and Israel's occupation of East Jerusalem.
Jerusalem remains at the core of the perennial Israel-Palestine conflict, as the Palestinians want Israeli-occupied East Jerusalem as the capital of a future state.