World leaders urged Israel against a full-scale invasion of Lebanon on Monday, September 30, and Tuesday, October 1, after its army said it had begun limited ground operations, in the latest step in its showdown with Hezbollah.

The two arch-foes have engaged in low-level clashes since the outbreak of war in Gaza, but tensions have skyrocketed in recent weeks as Israel shifted its focus to its northern border and staged a strike in which Hezbollah chief Hassan Nasrallah was killed.

UN: Avoid 'greater suffering'

After Israel said its troops were engaged in "limited raids" in Lebanon, the United Nations warned against those raids turning into a "large-scale ground invasion."

"The consequences for civilians have already been terrible," Liz Throssell, spokeswoman for the UN rights office, told reporters in Geneva. "We fear a large-scale ground invasion by Israel into Lebanon would only result in greater suffering."

While warning that Israel entering Lebanon would be "in violation of Lebanese sovereignty and territorial integrity," the UN peacekeeping force in south Lebanon told Agence France-Presse (AFP) that there was "no ground incursion right now."

US: Limited backing

US President Joe Biden indicated on Monday that he was opposed to Israel putting troops on the ground in Lebanon, adding: "We should have a ceasefire now."

However, late on Monday Defense Secretary Lloyd Austin gave Washington's backing to Israel for "dismantling attack infrastructure along the border."

Iran: No troops for Hezbollah

Though Hezbollah's key backer Iran had vowed Israel's "destruction" for the killing of Nasrallah, the militant group's leader, it said ahead of the Israeli operations that it would not deploy troops to Lebanon. "There is no need to send extra or volunteer forces of the Islamic Republic of Iran," said foreign ministry spokesman Nasser Kanani.

The same has applied to Gaza, where Israel has been locked in a war with Hamas – which is also backed by Tehran – since the Palestinian militant group's October 7 attack.

Russia: Immediate Israeli withdrawal

Russia, which has close ties with Iran, urged Israel "to immediately cease hostilities, withdraw their troops from Lebanese territory and engage in a real search for peaceful ways to resolve the Middle East conflict."

"We express our solidarity with the leadership and people of friendly Lebanon, which has been subjected to armed aggression," the Russian foreign ministry said.

China: 'Highly concerned'

In the wake of the Israeli announcement, China said it was "highly concerned about the escalation" and was opposed to "infringements on Lebanon's sovereignty, security, and territorial integrity."

A foreign ministry statement also warned against "any actions that exacerbate conflicts and lead to a further escalation of the regional situation."

Turkey: 'Unlawful invasion attempt'

A frequent critic of Israel's strikes on Lebanon and conduct of the war in Gaza, Turkey slammed Israel's ground offensive as an "unlawful invasion attempt."

"This attack must end as soon as possible and Israeli soldiers must withdraw from Lebanese territory," the foreign ministry said. "All state and international organizations, especially the UN, must stop Israel without wasting any more time," said President Recep Tayyip Erdogan, who added that Israel might even target Turkey.

Hezbollah: 'False claims'

However, Hezbollah itself denied that Israeli troops had crossed into Lebanon. "All the Zionist claims that (Israeli) occupation forces have entered Lebanon are false claims," a Hezbollah spokesman told the broadcaster Al-Jazeera in a statement that was then published on Hezbollah channels, adding there had "not yet been any direct ground clash between (Hezbollah) resistance fighters and (Israeli) occupation forces."

A source from the Lebanese army – whose capabilities are dwarfed by Hezbollah's military might – likewise said that it "had not observed any penetration by Israeli enemy forces into Lebanese territory."