Ayatollah Ali Khamenei issued the warning on Saturday after Israel struck Iran last week, killing at least five people.

Supreme Leader Ali Khamenei did not explicitly say an attack would originate from Iran, adding to speculation Tehran plans to retaliate from neighboring Iraq.

Ayatollah Ali Khamenei spoke as Iranian officials intensified threats of another strike against Israel, following its October 26 attack on Iran, which targeted military bases and other locations, resulting in at least five deaths.

The US and Israel "will definitely receive a crushing response", Iran's supreme leader has said, following an Israeli attack on Iran a week ago. Ayatollah Ali Khamenei made the comments while speaking to students on Saturday ahead of the 45th anniversary of the 1979 seizure of the US embassy in Tehran.

Threat by supreme leader raises concerns of wider regional conflict just ahead of the American presidential election this Tuesday.

"The enemies, whether the Zionist regime or the United States of America, will definitely receive a crushing response to what they are doing," Khamenei said.

Ayatollah Ali Khamenei warns Israel and the U.S. of 'a crushing response' over attacks on Iran and its allies as regional tensions rise.

Ayatollah Ali Khamenei's speech comes as rockets fired from Lebanon injured 11 people in central Israel, according to Israeli emergency services.

An attack on a central Israeli town early Saturday injured 11 people as Iran’s supreme leader vowed a punishing response to Israel’s attack last week and Israeli airstrikes continued in Gaza and Lebanon.

Iran’s Islamic Revolutionary Guard Corps said the country will “certainly” launch a new attack against Israel, a day after its supreme leader vowed a harsh retaliation.