On Thursday, US President Joe Biden and Israeli Prime Minister Yair Lapid signed a united vow to deny Iran nuclear weapons, demonstrating the allies' long-standing unanimity on negotiations with Tehran.

As part of a "Jerusalem Declaration" that capped Biden's first visit to Israel as president, the announcement came a day after he told a local TV station that he was open to a "last resort" use of force against Iran - an apparent move toward accommodating Israel's demands for a "credible military threat" from world powers.

Biden stated at a news conference following the signing of the declaration, "We will not allow Iran to acquire a nuclear weapon,"

Washington and Israel have separately hinted for years at a potential preemptive conflict with Iran, which denies seeking nuclear weapons. However, whether they have the capacity and motivation to accomplish this has been questioned.

The statement issued on Thursday underlined U.S. support for Israel's regional military superiority and ability to "defend itself by itself."

"The United States stresses that integral to this pledge is the commitment never to allow Iran to acquire a nuclear weapon, and that it is prepared to use all elements of its national power to ensure that outcome," the statement continued.

Lapid presented this stance as a means of avoiding open conflict.

After the signing ceremony, he stated, "The only way to stop a nuclear Iran is if Iran knows the free world will use force,"

President Joe Biden described stopping a nuclear Iran as "a vital security interest for Israel and the United States and, I would add, for the rest of the world as well."

Tehran provided no immediate comment.

Iran signed an international agreement in 2015 restricting its nuclear programs with bomb-making potential. In 2018, the then-president of the United States, Donald Trump, withdrew from the accord, citing its insufficiency, which Israel welcomed.

Iran has subsequently increased its nuclear activities, making it more difficult for world powers to return to an agreement in Vienna. Israel now says it would approve a new deal with stricter terms, and Iran has refused to accept additional restrictions.

Sanctions pressure

Biden has advocated for a resumption of negotiations, but Iran is responsible for its response.

He stated, "We are not going to wait forever,"

Beyond bolstering the allies' sense of deterrence and mutual commitment, Biden may receive a boost from Thursday's force projection when he travels to Saudi Arabia on Friday. Biden intends to leverage Riyadh's Iran concerns into a Saudi-Israeli reconciliation under U.S. auspices.

Biden told reporters that he and Lapid had addressed the significance of "for Israel to be integrated into the region" Lapid, in turn, termed Biden's Saudi trip "extremely important to Israel."

The Islamist party Hamas, which has helped lead the Palestinian resistance against Israel, condemned the moves.

Ismail Haniyeh, the chairman of Hamas, made a statement urging the development of "a political alliance to protect the region from dominance, normalization, and the theft of its wealth."

Some Israeli and Gulf Arab officials think the nuclear deal's sanctions relief will provide Iran with significantly more funds to finance proxy troops in Lebanon, Syria, Yemen, and Iraq. They are also pessimistic that the Biden administration will substantially challenge Iran's regional actions.

When asked if Thursday's remark was intended to buy time with Israel while Washington continues negotiations with Iran, a U.S. official stated, "If Iran wants to sign the deal that has been negotiated in Vienna, we have made it quite clear that we are willing to do so. Moreover, if they do not, we will continue to increase sanctions pressure and Iran's diplomatic isolation."

The Jerusalem Declaration also committed the United States and Israel to work on military and civilian technologies, such as laser interceptors.

The statement added that the United States is interested in reopening talks on an Israeli-Palestinian two-state solution, reiterating Washington's willingness to provide Israel with future defense assistance.