Iran has likely become more susceptible to pressure in talks with world powers on a nuclear deal since Sunni militants took over a wide swath of Iraq last week, placing a military threat at its doorstep, a senior Israeli official told The Times of Israel on Tuesday.

As six world powers engaged in a fresh round of talks with Iran this week, the Israeli official urged them to take advantage of the fact that Iran feels beleaguered by Islamic State of Iraq and the Levant, better known as ISIL or ISIS, and take a tougher stance regarding the regime’s rogue nuclear program.

“The Iranians are under pressure. They are very concerned about what is going in Iraq and the possibility that they will face a very hostile regime on their western border,” said the senior official, who was speaking on the condition of anonymity. “This is the time for the international community to use its leverage on Iran and demand the dismantlement of its military nuclear program. Today because of what’s happening in Iraq, the leverage has been greatly enhanced.”

ISIL forces captured a large piece of Iraq’s heartland over the last several days and fighters were advancing toward Baghdad — currently ruled a by a Shiite-friendly government — putting Tehran on edge.

The international community, though, has thus far taken a tack of embracing rather than pressuring Iran, seeking a resolution to the nuclear question while simultaneously gaining a powerful ally in the fight against the jihadi threats from ISIL and its allies.

US officials said they briefly discussed Iraq with Iran, on the sidelines of nuclear talks currently taking place in Vienna, but emphasized that it intends to keep the two issues separate.

Tehran and Washington “have a shared concern about the threats from ISIL,” State Department spokesperson Jen Psaki said Monday. “We’re open to talking to Iran about the situation in Iraq, just as we’re talking to all of Iraq’s neighboring states.”

Also on Tuesday, British Foreign William Hague announced that the United Kingdom is going to reopen its embassy in Tehran, a sign of warming ties between the countries. “Over the past four months, we have continued to expand our bilateral engagement,” Hague declared in a written statement. “Iran is an important country in a volatile region, and maintaining Embassies around the world, even under difficult conditions, is a central pillar of the UK’s global diplomatic approach.”

The so-called P5+1 — Britain, the US, France, China, Russia and Germany — on Tuesday launched talks with Iran, trying to secure a permanent deal over the Islamic Republic’s nuclear program before the July 20 deadline set when the Geneva interim agreement went into effect.

Israel is staunchly supposed to any agreement that would leave Tehran with the ability to enrich uranium, a position at odds with the P5+1, which appear willing to let Tehran retain some level of enrichment capacity.

Regarding the situation in Syria and Iraq, Jerusalem has remained vague. Israel’s defense establishment is divided on whom it supports in the war between Sunni and Shiite forces, which is currently spreading through the region.

Some lean toward Syrian President Bashar Assad and Iraqi Prime Minister Nuri al-Maliki — both virtual puppets of Iran, because Sunni extremist victories would further destabilize the region and imperil Jordan and Saudi Arabia.

Others, like former head of military intelligence Amos Yadlin, believe that a Sunni victory next door “may make life more difficult for the brigade commander on the Golan or for the division commander responsible for guarding the border. But from the point of view of the prime minister’s office and the Defense Ministry, [Assad's ouster] would be a very positive strategic development,” he told The Times of Israel in May.

Mitch Ginsburg contributed to this report.