The Israel Defense Forces on Tuesday accused the Iranian military of violating the ceasefire that had come into force only hours before.

Tel Aviv will “respond with force” in retaliation to the “severe violation of the ceasefire carried out by the Iranian regime”, said Israeli Chief of General Staff Eyal Zamir.

However, Iranian state-run Press TV quoted the country’s armed forces as having denied that it had launched fresh missile attacks on Israel.

United States President Donald Trump said that both Israel and Iran violated the terms of a ceasefire, the Associated Press reported.

Speaking to reporters at the White House before heading to the North Atlantic Treaty Organization summit in The Hague, Trump said: “They violated it but Israel violated it too.”

“I am not happy with Israel,” he added.

In a social media post, Trump urged Israel not to drop bombs on Iran.

“Israel. Do not drop those bombs,” he said. “If you do it is a major violation.”

Meanwhile, Israeli Defence Minister Israel Katz said that he had ordered the military “to respond forcefully to Iran’s violation of the ceasefire by launching powerful strikes against regime targets in the heart of Tehran”, AFP reported.

The Israeli forces at 10.35 am local time said that sirens were being sounded in northern Israel “due to missile fire” from Iran.

Iran’s Supreme National Security Council said on Tuesday that its armed forces had compelled Israel to “unilaterally halt its aggression”, AFP reported.

The military remained “on high alert” to respond to “any act of aggression”, the country’s top security body added.

The alleged violation of the ceasefire by Iran came hours after Tel Aviv and Tehran agreed to the truce after 12 days of conflict.

Trump had first made the announcement on social media, saying that Iran and Israel had agreed to a “complete and total” ceasefire.

Iran’s Foreign Minister Seyed Abbas Araghchi initially said that there had been no agreement on a ceasefire. However, he added minutes later that the Iranian military operation “continued until the very last minute”, till 4 am local time.

State-run Press TV channel reported at 7.49 am Iranian time that the ceasefire had taken effect.

Israeli Prime Minister Benjamin Netanyahu’s office confirmed that the country had agreed to a proposal by the US for a ceasefire with Iran.

However, the prime minister’s office said that Israel will “respond forcefully” to any violations of the agreement.

Trump’s announcement came hours after Iran struck the Al Udeid Air Base in Qatar, which houses US troops. The US president said no Americans or Qataris were killed or wounded in the attack.

On June 13, the Israeli military struck what it claimed were nuclear targets, and also other sites, in Iran with the aim of stalling Tehran’s nuclear programme. Iran retaliated with missile attacks on Israel.

While Israel has claimed that Iran was “closer than ever” to obtaining a nuclear weapon, Iran has long maintained that its nuclear programme is for civilian purposes.

The US joined Israel’s war against Iran in the early hours of Sunday. Trump had said that the country carried out a “very successful attack” on Iranian nuclear sites in Fordo, Natanz and Esfahan.

Washington is an ally of Israel and acts as a guarantor of the country’s security.

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