President Obama hopes to announce his new national security nominees Friday, but the date depends on the status of the “fiscal cliff” negotiations, administration officials said.

Other White House business has taken a back seat to talks with Republicans to avert the cliff — a set of mandatory spending cuts and tax increases — before the Dec. 31 deadline, the officials said. Obama may also postpone his scheduled Friday departure for his holiday vacation in Hawaii.

The announcement may also be delayed because of Secretary of State Hillary Rodham Clinton’s illness, although her presence at a public presentation of the nominees is not a prerequisite, according to the officials, who spoke on the condition of anonymity about administration planning. Clinton is recovering from a stomach virus and a concussion.

While the likely choices for top Cabinet posts — Sen. John F. Kerry (D-Mass.) as secretary of state and former senator Chuck Hagel (R-Neb.) as defense secretary — are seen as confirmable by the Senate, neither is without opponents.

Republican criticism of U.N. Ambassador Susan E. Rice was allowed to build for months, from the time she became widely rumored as Obama’s first choice for secretary of state to her withdrawal from consideration last week.

Kerry and Hagel have already drawn questions in Israel. An article Monday on Ynet, that country’s most popular online news site, noted that while Kerry is considered a “friend of Israel,” he has been sharply critical of the government’s settlement policy.

The headline on an analysis in Monday’s Jerusalem Post read: “Kerry and Hagel: Hardly Israel’s preferred choices.”

In this country, Hagel’s perceived views on Israel and relations with Iran have prompted critical commentary from some political quarters. A few prominent Jewish Democratic activists have complained to the White House about Hagel, including at a White House Hanukkah party last week, according to participants.

Most of the discomfort on both sides of the party line centers on Hagel’s voting record, during his two terms in the Senate, against tougher sanctions on Iran as a way to curb that nation’s nuclear program, which Israel sees as an existential threat. During the George W. Bush administration, Hagel, who did not seek a third term in 2008, repeatedly spoke against a military strike on Iran’s nuclear program and called for diplomatic engagement.

“The White House is underestimating how much fury will be released on Hagel for his Iran views,” a senior Republican Senate aide said. The aide added that “groups are already cutting TV spots to run against Hagel.”

The administration has tried to both negotiate with Iran and impose tougher sanctions, saying that sanctions can pave the way for more meaningful talks. But the sanctions approved after Hagel left the Senate have not forced Tehran to bargain, resulted in substantive negotiations or curbed Iran’s enrichment of uranium.

In a Washington Post op-ed in September, Hagel echoed Obama’s policy on the importance of keeping “all options on the table, including the use of military force” in dealings with Iran.