Iran warned Israel of escalation if it failed to end aggressions against Palestinians, with its foreign minister saying other parties in the region were ready to act, the semi-official Fars news agency reported on Sunday.
"If the Zionist aggressions do not stop, the hands of all parties in the region are on the trigger," Hossein Amirabdollahian was quoted as saying.
Israel's Prime Minister Benjamin Netanyahu vowed on Sunday to "demolish Hamas" as his military prepared to move into the Gaza Strip in search of Islamist militants whose deadly rampage through Israeli border towns shocked the world.
Iran's top authority, Supreme Leader Ayatollah Ali Khamenei, said on Tuesday Tehran was not involved in the militant Hamas group's attack on Israel, but hailed what he called Israel's "irreparable" military and intelligence defeat.
Israel has long accused Iran's clerical rulers of stoking violence by supplying arms to Hamas. Tehran says it gives moral and financial support to the group, which controls the Gaza Strip.
Backing the Palestinian cause has been a pillar of the Islamic Republic since the 1979 revolution and a way the Shi'ite-dominated country has fashioned itself as a leader of the Muslim world.
Amirabdollahian, who last week accused Israel of seeking "genocide" by enforcing a siege against the Gaza Strip, said an attack on Gaza would "open new fronts of resistance" in the Middle East.
"The responsibility for the possible opening of new fronts of resistance in the region and any escalation of today's war directly falls on the United States and the Zionist regime (Israel)," Amirabdollahian said.
Amirabdollahian met with Hamas leader Ismail Haniyeh on Saturday in Qatar, where they discussed the group's deadly attack in Israel "and agreed to continue cooperation" to achieve the group's goals, the Iran-backed Hamas said in a statement.
Earlier, Iran's President Ebrahim Raisi urged France to help "prevent oppression" of Palestinians in a phone call with his counterpart, Emmanuel Macron.
