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For President Joe Biden, a The attack on Israel was launched from Iranian territory It amounts to the scenario he has desperately sought to avoid since the beginning of the current conflict in the Middle East.

These retaliatory actions increase the risk of a broader regional conflict that could directly draw the United States alongside other countries.

They put Biden – once again – in the vulnerable position of pledging strong support for Israel while also trying to prevent a new conflagration involving the United States.

What comes next is unknown. In the immediate aftermath of the Iranian attacks, US officials admitted that they had entered uncharted territory, and the extent of the Iranian attacks was initially unclear. One important question mark is how proxies might join Iranian efforts to target Israel and add a new layer of unpredictability. As Israel's response plans continue to take shape, Biden administration officials are expected to continue to advise their Israeli counterparts — keeping the desire for containment in mind.

Biden is also working within tense politics Election yearWhich gives great importance to his future decisions. eruption Israel-Hamas war The October 7 election hurt Biden at home, eroding his support in key constituencies as he refused to call for a permanent ceasefire in Gaza.

One official said one reason Biden urgently returned to the White House from his beach house in Delaware on Saturday afternoon was the ongoing nature of the attack, as the situation room is better equipped to monitor events in real time.

A US official told CNN that administration officials saw the Iranian attacks on Israel on Saturday as disproportionate to the Israeli strikes in Damascus that led to retaliation.

This view was an important factor in discussions at the White House throughout the day about next steps, especially since Biden is determined to prevent a large-scale regional conflict.

The official added that there is also a recognition that what Israel is likely to do in response will depend on a full assessment of the damage, including potential casualties, and so the Biden administration's advice to Israel will depend on that picture emerging.

Biden and Israeli Prime Minister Benjamin Netanyahu spoke on Saturday evening, as did Defense Secretary Lloyd Austin and his counterpart Yoav Gallant, and the two governments will remain in close contact in the coming hours and days.

In the wake of Israeli strikes in Syria that killed top Iranian leaders, US officials watched as Iran prepared to launch a major attack on Israel, seeing it as inevitable. While the United States, in close consultation with Israel, has sought to know exactly how, when and where Iran will retaliate, administration officials have not completely ruled out an Iranian attempt to strike inside Israel as well as US personnel and assets in the region.

A senior administration official said in the days before Saturday's Iran attacks that the most likely “worst-case scenario” was a direct attack by Iran on Israel, and a state-to-state conflict that could lead to outright war. The beginning of a broader regional conflict that the United States has been working to prevent since the attacks launched by Hamas on October 7th.

Despite current tensions with Netanyahu over the war in Gaza, Biden and his senior officials sought over the past week to reduce any rift between the United States and Israel when it comes to Israel's defense against Iran.

In the hours before Iran launched its attack, the US Secretary of Defense and National Security Advisor spoke with their counterparts in Israel to confirm this support. Last week, General Eric Kurella, commander of US Central Command, was in Israel to discuss contingencies with officials ahead of the expected attack.

Biden kept his promise on Friday that “the United States is committed to defending Israel,” with defense officials telling CNN that the US military successfully intercepted some Iranian missiles on Saturday.

Officials familiar with the matter said that the talks on preparations for the Iranian attack and coordination of the response also included implicit encouragement for the Israeli government not to let the situation get out of control if Iran's response was limited in nature.

The United States also sent public and private messages to Iran warning against further escalation of the crisis, and pressured European and Arab allies to use their influence with Tehran to deliver similar messages.

As Iran's plans to attack Israel become clearer, American officials increasingly assess that Tehran does not seek direct conflict with the United States. Before Iran's drone attack on Saturday, US officials said they did not expect the targets to include US forces in the region.

This is a change from earlier in the conflict, when Iranian-backed militias regularly attacked US forces in the Middle East, including a raid that killed three Americans stationed in Jordan. After the United States launched retaliatory strikes, Iranian proxy attacks diminished.

However, the escalating tensions between Iran and Israel have not subsided. In the absence of any direct channels of communication between the two countries, the risk of miscalculation is magnified.

CNN's Oren Lieberman contributed reporting.