A key ally of Donald Trump has urged the US to consider attacking Iran in response to the drone attacks on Saudi Arabia’s oil industry.

Republican senator Lindsey Graham, a prominent foreign policy hawk, suggested that hitting the country’s own refineries would “break the regime’s back”.

“Iran will not stop their misbehaviour until the consequences become more real,” he tweeted on Saturday night.

Mr Graham added: “Iranian supported Houthi rebels who attacked Saudi oil refineries is yet another example of how Iran is wreaking havoc in the Middle East. The Iranian regime is not interested in peace – they’re pursuing nuclear weapons and regional dominance.

“It is now time for the US to put on the table an attack on Iranian oil refineries if they continue their provocations or increase nuclear enrichment.”

US secretary of state Mike Pompeo also blamed Iran for the attacks on the world’s largest oil processing facility in Buqyaq and an oilfield in Khurais, which cut Saudi Arabia’s crude oil supply by around 50 per cent.

The Islamic Republic of Iran 40 years on Show all 20 1 /20 The Islamic Republic of Iran 40 years on The Islamic Republic of Iran 40 years on Women praying during Ashura festivities in Yazd in February Jan Schneider The Islamic Republic of Iran 40 years on Cars cemented in at the Holy Defence Museum-Garden in Khorramshahr – in 1980 occupying Iraqi forces used such formations to deter paratrooper landings Jan Schneider The Islamic Republic of Iran 40 years on Women on the Si-o-se-pol bridge over the Zayanderude river in Esfahan Jan Schneider The Islamic Republic of Iran 40 years on Iranian tourists at Vank cathedral in the Armenian quarter in the city of Esfahan Jan Schneider The Islamic Republic of Iran 40 years on A reddened fountain in Yazd – a national motif recalling the countries ‘martyrs’ Pictures by Jan Schneider The Islamic Republic of Iran 40 years on Prayers before a list naming the fallen of the Iran-Iraq war in Tehran Jan Schneider The Islamic Republic of Iran 40 years on In a museum in central Tehran, a wax figure of Ayatollah Khomeini Jan Schneider The Islamic Republic of Iran 40 years on Carom billiards in Tehran Jan Schneider The Islamic Republic of Iran 40 years on Nearly two thirds of Iran’s population is under-30 Jan Schneider The Islamic Republic of Iran 40 years on Sanctions are exacerbating poverty Jan Schneider The Islamic Republic of Iran 40 years on Young people are adept at catching moments of freedom, such as this one in the capital Jan Schneider The Islamic Republic of Iran 40 years on At an art auction in Tehran, the wealthy turn out Jan Schneider The Islamic Republic of Iran 40 years on Propaganda murals are everywhere Jan Schneider The Islamic Republic of Iran 40 years on Tehranis love their outdoor spaces too Jan Schneider The Islamic Republic of Iran 40 years on The hypersaline waters of Lake Urmia are fast diminishing – Iran faces ecological catastrophe Jan Schneider The Islamic Republic of Iran 40 years on A martyr is depicted outside the huge Beheshte-e-Zahra cemetery in Tehran Jan Schneider The Islamic Republic of Iran 40 years on A guard naps outside Iran’s foremost tourist attraction – the ancient ruins of Persepolis Jan Schneider The Islamic Republic of Iran 40 years on Memorial to Iranian pilgrims who died during a stampede in Mecca 1987 Jan Schneider The Islamic Republic of Iran 40 years on The martyr fixation on display in the southern city of Shush Jan Schneider The Islamic Republic of Iran 40 years on Emamzadeh Saleh mosque in Shemiran, Tehran Jan Schneider

Mr Pompeo insisted there was “no evidence the attacks came from Yemen”, even though Yemen’s Houthi rebels claimed responsibility for the strikes.

“Amid all the calls for de-escalation, Iran has now launched an unprecedented attack on the world’s energy supply,” he said, adding that the US would ensure that “Iran is held accountable for its aggression”.

The growing clamour for a confrontation with Iran comes just five days after the president sacked his national security adviser John Bolton, who was an outspoken advocate of regime change. It had even been suggested that Mr Trump was interested in renegotiating a new deal with the Middle Eastern country.

Iran rejected Mr Pompeo’s statement as “maxium lies” and asserted that it “has always been ready for a ‘full-fledged war’”.

“Everybody should know that all American bases and their aircraft carriers in a distance of up to 2,000km around Iran are within the range of our missiles,” the head of Iran’s Revolutionary Guards Corps Aerospace Force, Amirali Hajizadeh, said on Sunday.

Saudi Arabia claims Iran is arming the Houthi rebel group and has blamed its regional rival for previous attacks. It intervened in the Yemen civil war against the Houthis in 2015 and the conflict is now regarded as the world’s worst humanitarian crisis.

However, critics of the Trump administration’s decision to blame Iran described it as an “irresponsible simplification”, with some speculating that the recent departure of John Bolton as national security adviser has increased the risk of armed conflict with the country.

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“It’s how we get into dumb wars,” said Democratic senator and committee member Chris Murphy. “Iran is backing the Houthis and has been a bad actor, but it’s just not as simple as Houthis equals Iran.”