LONDON, Sept 26, 2024 (BSS/AFP) - US Defense Secretary Lloyd Austin warned Thursday that "all-out war" would be "devastating" for Israel and Lebanon, but that a ceasefire could buy time to stop the Gaza conflict.

"A full scale war between Hezbollah and Israel could be devastating for both parties," Austin said in London after meetings with his UK and Australian counterparts in the AUKUS military alliance.

Austin called on both sides to "choose a different path", saying that "despite the sharp escalation, a diplomatic solution is still viable".

Such an outcome is "the only way to ensure that displaced civilians on both sides of the border can finally go home," he said.

US President Joe Biden and other world leaders have called for an immediate, 21-day ceasefire in hostilities between Israel and Hezbollah. Israel's foreign minister rejected the proposal.

A pause in hostilities would "provide time" for a deal to be struck that would allow Israel and Lebanese civilians to return home, Austin told a news conference after the talks of the trilateral defence partnership.

This time could also be used "to conclude and implement a deal to secure a ceasefire in Gaza and to bring all the hostages home," said Austin.

"We recognise that there's hard work to be done. We are committed to doing that work, and yes, I am optimistic," he added.