U.S. envoy Amos Hochstein said Wednesday he believed all-out war between Israel and Lebanon's powerful terrorist group Hezbollah could be avoided but that Israel and Hamas needed to move toward a peace agreement for Gaza without further delay.

Iran-backed Hezbollah began cross-border attacks on Israel soon after Israeli forces began a military assault on Gaza in response to the deadly Hamas attack on Israel on Oct. 7. Israeli fire, initially confined to Lebanon's border area, has now targeted senior Hezbollah, Hamas and other figures further north.

Hochstein, a senior adviser to President Joe Biden, landed in Beirut on Wednesday to deter an escalation between Hezbollah and Israel, after the latter killed a senior Hezbollah commander in Beirut's southern suburbs last month.

"We continue to believe that a diplomatic resolution is achievable because we continue to believe that no one truly wants a full-scale war between Lebanon and Israel," Hochstein said after talks with parliament speaker Nabih Berri, a strong Hezbollah ally.

Hochstein said he talked with Berri about the framework agreement on the table for a Gaza ceasefire, adding that deal would also help enable a diplomatic resolution in Lebanon that would prevent an outbreak of a wider war.

"He [Berri] and I agreed there is no more time to waste and there's no more valid excuses from any party for any further delay," he told a news conference.

Hochstein is also due to meet with Lebanese caretaker Prime Minister Najib Mikati and foreign minister Abdullah Bou Habib.

Earlier on Wednesday, Mikati said talks with Arab and Western leaders had intensified due to the seriousness of the situation in Lebanon and the region.

"We are facing uncertain opportunities for diplomacy which is now moving to prevent war and stop Israeli aggression," Mikati said in a speech ahead of a cabinet meeting Wednesday.

When asked by a reporter whether Israel and Hezbollah could avoid a war, Hochstein replied: "I hope so, I believe so."