JERUSALEM — President Mahmoud Abbas of the Palestinian Authority on Thursday asked Rami Hamdallah, the prime minister, to form a new government of national reconciliation, a move that could send Israeli-Palestinian relations into a tailspin and would disrupt any prospect of a resumption of US-brokered peace talks.
The decision to form a new government is the result of a unity pact reached last month between Abbas’s Palestine Liberation Organization, which is dominated by the mainstream Fatah faction, and its rival, Hamas, the Islamic militant group that controls Gaza. Palestinian officials said the new government, made up of politically independent professionals, would probably be announced within days.
Under the terms of the agreement last month, Palestinian leaders agreed to do that within five weeks, and elections were to be held in about six months
“This letter designates Dr. Rami Hamdallah to form a new transitional government,” Abbas said Thursday, according to WAFA, the official Palestinian news agency, at an appearance with Hamdallah. “I wish him luck in this difficult task.’’
The possibility has already prompted stern warnings from Israel, which says it will not deal with a government “backed by Hamas,” even if the ministers themselves are not politically affiliated. Hamas has refused to recognize Israel, which, like the United States and the European Union, classifies Hamas as a terrorist organization.
A Palestinian consensus government could also prove to be a new source of tension between Israel and the Obama administration, because of possible differences over how to deal with the new government.
“We think that by embracing Hamas, Abbas is increasing the levels of volatility and danger,” an Israeli government official said, requesting anonymity because he was speaking before a new Palestinian government had formally been announced. “We are concerned that Hamas will exploit the pact to strengthen its position in the West Bank.”
Sami Abu Zuhri, a Hamas spokesman in Gaza, said a few more days were needed to finalize the government.
Other officials suggested that one or two ministerial appointments were still in dispute.
But the Israeli official added that once Abbas “consummates” his alliance with Hamas, he could be held accountable for any rockets fired against Israel by militants in Gaza.
“He will become an address for our response,” the official said, refusing to elaborate.
The European Union, which gives substantial aid to the Palestinian Authority, has said it will support a new government of independent figures and continue direct financial assistance so long as the government upholds international principles of nonviolence, accepts previous obligations and agreements with Israel, and recognizes Israel’s right to exist.
Abbas has said that the government will adhere to these conditions. That is not enough for Israel, which insists on Hamas adhering to them as well.
Israeli officials have said that they received a specific commitment in the past from the US administration that it backed Israel’s position of not negotiating or dealing with a government in which Hamas played a role unless Hamas accepted the principles laid down by world powers after the Islamic group won Palestinian elections in 2006.
But that claim appeared to be at odds with some more recent signals from Washington.
After the Palestinians announced their unity deal in April, Jen Psaki, a State Department spokeswoman, called the move “disappointing.”
She then added that “any Palestinian government must unambiguously and explicitly commit to nonviolence, recognition of the state of Israel, and acceptance of previous agreements and obligations between the parties,” without making any mention of Hamas.
“Clearly there are differences of opinion between Israel and the United States,” said Michael Herzog, a fellow of the Washington Institute for Near East Policy and a former military official and negotiator based in Israel.
“Even if there were such understandings,” he said, referring to the Israeli assertions about a past commitment, “the US is not there today.”