A key adviser to President Biden arrived Monday in Israel to continue efforts to de-escalate in the region and to avoid a second front in Israel’s war against Hamas.

National security spokesperson John Kirby confirmed at a briefing Monday that senior energy adviser Amos Hochstein was in Israel to speak with Israeli counterparts over concerns that Hezbollah in southern Lebanon could join a wider war.

“We don’t want to see this war escalate. We don’t want to see it widen. We certainly don’t believe it’s in anybody’s interest, certainly not the Israeli people’s interest to have a second front there in the north,” Kirby told reporters.

“Though what Amos is doing, what our team is doing, is everything we can to help prevent that scenario from happening,” Kirby added.

Kirby described Hochstein’s decision as a “sort of back briefing,” following up on discussions he had a week or so ago, “where he talked to Lebanese officials and to Israeli officials up in the north about the risks of a second front, a Northern Front.”

Hochstein led quiet negotiations last year on an agreement on maritime borders between Israel and Lebanon.

Hochstein’s latest trip comes as tensions continue to flare on the northern border of Israel and the southern border of Lebanon, where Hezbollah, a U.S.-designated terrorist organization, holds significant power.

There is already a regular exchange of fire on the border, and officials have expressed concern that the flare-ups could lead to a second front against Hezbollah, which is widely regarded as more powerful and threatening to Israel’s existence than Hamas, another U.S.-designated terrorist organization. Both groups are backed by Iran.

Hamas launched a surprise attack on the southern border of Israel on Oct. 7, killing 1,200 Israelis and taking about 240 hostages. Iran has claimed no previous knowledge of the plans. Israel responded with a barrage of airstrikes and a ground invasion that has moved into Gaza City. According to the Hamas-run health ministry in Gaza, more than 11,000 Palestinians have been killed so far in the war.

“We don’t want to see the conflict widen, escalate. That is why Amos is having the conversations he’s having,” Kirby said.

“That’s why Secretary Blinken has now had two extensive trips to the Middle East. And it’s why the President has put forward additional force posture,” he added.

Kirby pointed to “the carrier strike groups, but also air and missile defense as well as fixed-wing aviation into the region, so that we can send a strong signal to any actor, nation-state or otherwise, that if you’re going to think about widening and deepening this conflict, don’t do it.”