Iran warned Monday of a possible "pre-emptive action" against Israel "in the coming hours", as Israel readies for a ground offensive on the Gaza Strip.

Tehran has repeatedly warned that a ground invasion of the long-blockaded Gaza would be met with a response from other fronts — prompting fears of a wider conflict that could draw in other countries.

"The possibility of pre-emptive action by the resistance axis is expected in the coming hours," Iran's foreign minister, Hossein Amir-Abdollahian said in a live broadcast to state TV, as he referred to his meeting with Hezbollah leader Hassan Nasrallah on Saturday.

Earlier Monday, Iran's top diplomat and president, Ebrahim Raisi had said time was running out to reach a political solution and warned against the expansion of the Israel-Hamas war to other fronts.

Amir-Abdollahian said Monday that "the resistance leaders" will not allow Israel "to do whatever it wants in Gaza".

"If we don't defend Gaza today, tomorrow we have to defend against these (phosphorus) bombs in the children's hospital of our own country," he added.

Israel declared war on the Palestinian Islamist group Hamas a day after waves of its fighters broke through Gaza's heavily militarised border with Israel on October 7 and killed over 1,400 people, most of them civilians.

Israel has responded by pummelling the Gaza Strip with non-stop air and artillery strikes that have flattened neighbourhoods and killed at least 2,750 people in Gaza, mostly civilians.

Iran celebrated the Hamas assault but insisted it was not involved.

The Monday remarks come as Israel prepares for a ground invasion into the Gaza Strip, where fears for Palestinians trapped in the heavily-bombarded enclave have grown since Israel launched its aerial campaign.

Since its Islamic revolution in 1979, Iran has made support for Palestinians one of the pillars of its ideology.