President Barack Obama will call off his imminent visit to Israel if Prime Minister Benjamin Netanyahu has not managed to form a new governing coalition by March 16, an Israeli television report claimed on Thursday night.

Obama is due to arrive in Israel on March 20 for a working visit, his first as president. March 16 is the legal deadline for Netanyahu to successfully complete coalition negotiations, or inform Israel’s state president, Shimon Peres, that he has failed to do so.

Confirming the trip almost four weeks ago, Israeli and US officials made clear that the president was timing the visit so as to ensure Israel would have a new government in place by the time he arrived. Israel held elections on January 22; Netanyahu’s Likud-Beytenu emerged as the largest slate, and Netanyahu was formally charged with the task of building a coalition on February 2. The assumption was that he would have mustered a viable majority ahead of the president’s arrival.

But Netanyahu’s efforts to cobble together a stable coalition have been immensely complicated by an alliance between the Jewish Home and Yesh Atid parties, which are working together to demand new legislation to draft most ultra-Orthodox males into military or national service. The ultra-Orthodox parties are opposed to so drastic a change, and Netanyahu has thus far been unable to resolve this and other differences between his potential coalition parties. His chief negotiator, David Shimron, said Thursday that Yesh Atid stated flatly in their latest talks that it saw “no place” for the ultra-Orthodox in the next government.

On Saturday night, Netanyahu will have used up the 28 days he was given by Peres to form a government, and he has scheduled a meeting with the president at which he will be granted a 14-day extension, taking him through to March 16. No further extension is legally permitted.

If Netanyahu has not managed to form a coalition by then, Israel’s Channel 10 news reported quoting unnamed American sources, Obama will cancel his visit, set to start four days later.

The same report also claimed that the US hoped to see Yesh Atid’s leader, former TV news anchor Yair Lapid, take the post of foreign minister in the next coalition.

The enforced cancelation of Obama’s first visit to Israel as president would be hugely embarrassing for the Jewish state, whose leaders have long urged Obama to come. Israel’s alliance with the United States is by far its most important international partnership. The two leaderships have said they would consult on efforts to thwart Iran’s nuclear drive, the instability in Syria, ways to revive peace talks with the Palestinians, and other vital issues.

Beyond the implications for the presidential visit, a failure to form a coalition by March 16 would require Peres to charge a different politician with the task of forming a government. If that proved impossible, Israel would have to hold another round of elections.

As of Thursday night, with his various potential coalition partners deeply at odds, Netanyahu had signed up only Tzipi Livni’s six-seat Hatnua party to his coalition, and the differences between the other parties appeared very hard to reconcile. But were Netanyahu to decide to exclude the ultra-Orthodox parties, however reluctantly, his Likud-Beytenu party (31 seats) could expect to finalize coalition terms with Yesh Atid (19 seats) and Jewish Home (12 seats) fairly rapidly, and thus gain a governing majority. In that way, he would safeguard both his prime ministership and the Obama visit.