US Secretary of State Mike Pompeo today ratcheted up the Trump administration's rhetoric against Iran and gave warm boosts of support to Israel and Saudi Arabia in their standoffs with Tehran.
Pompeo's comments in Riyadh and then Tel Aviv came as he neared the end of the Middle East leg of his first trip abroad as America's top diplomat.
He has called for concerted international action to punish Iran for its missile programmes and other actions that he said destabilise the region.
The tough line was welcomed by his hosts, particularly in Israel, which considers Iran its greatest threat and has led calls for the West to revise or reject the 2015 nuclear deal with Iran.
"We remain deeply concerned about Iran's dangerous escalation of threats to Israel and the region, and Iran's ambition to dominate the Middle East remains," Pompeo said after a nearly two-hour meeting with Israeli Prime Minister Benjamin Netanyahu.
"The United States is with Israel in this fight."
Israel has cited Iran's hostile rhetoric, support for anti-Israel militant groups and development of long-range missiles.
It also has complained the nuclear deal does not do enough to prevent Iran from developing a nuclear-weapons capability, and expressed concerns about Iran's involvement in the civil war in neighbouring Syria.
Israel says it will not allow Iran to establish a permanent military presence in Syria, fearing the Iranians will use it to launch attacks.
"Iran must be stopped, its quest for a nuclear bomb must be stopped, its aggression must be stopped and we're committed to stopping it together," Netanyahu said.
President Donald Trump is to decide by May 12 whether to keep the US in the nuclear deal.
Pompeo repeated the Trump position that "if we can't fix it, he is going to withdraw".
Saudi foreign minister Adel al-Jubeir said the kingdom "supports the policy of the Trump administration against Iran and to improve the terms of the nuclear agreement with Iran".
Netanyahu also welcomed the US recognition of Jerusalem as Israel's capital and the scheduled move of its embassy from Tel Aviv on May 14.
Pompeo said the US is "incredibly proud" of that forthcoming move.
Pompeo had no meetings planned with any Palestinian official and it was not clear whether there had been any outreach to the Palestinians about his trip, which was to end in Jordan on Monday.
In Riyadh, Pompeo said Iran "destabilises this entire region" and he also urged the Saudis and their neighbours to resolve a festering dispute with Qatar.
US officials say Iran is exploiting it to boost its influence in the region, including in Yemen and Syria.
Pompeo met Saudi King Salman, whose country, along with Bahrain, Egypt and the United Arab Emirates, is embroiled in a row with Qatar that had undermined Gulf Arab unity and frustrated the US as it seeks to blunt growing Iranian assertiveness.
"I think they would all agree that it's in everyone's best interests that the Gulf states all figure out how to be together," Pompeo told reporters as he travelled to Israel.
"We've got a common challenge in Iran I think they all recognise that. We're hopeful that they will in their own way figure out their dispute between them."