Well that didn't take long.

Just two days after being sworn in as US Secretary of State, former CIA Director Mike Pompeo arrived in Saudi Arabia on Saturday on a hastily-arranged visit to the Middle East to reinvigorate support for new sanctions against Iran.

As Reuters reports, the visit to Riyadh, Jerusalem and Amman comes as President Trump is set to decide whether to pull out of the 2015 nuclear deal with Iran that is still supported by European powers.

“We are urging nations around the world to sanction any individuals and entities associated with Iran’s missile program, and it has also been a big part of discussions with Europeans,” Brian Hook, a senior policy advisor traveling with Pompeo, told reporters. “Iran’s missiles prolong war and suffering in the Middle East, they threaten our security and economic interests and they especially threaten Saudi Arabia and Israel,” he added.

Following Macron's earlier-in-the-week efforts to persuade Trump not to kill the Iran deal, Pompeo told a news conference:

“There’s been no decision, so the team is working and I am sure we will have lots of conversations to deliver what the president has made clear."

In Riyadh, Pompeo was greeted on the tarmac by Saudi Foreign Minister Adel al-Jubeir. He is expected to meet Saudi Crown Prince Mohammed bin Salman and King Salman during the visit.

But as Patrick Coburn writes at Counterpunch.org, as the Trump administration begins to berate Iran once again, their options may be more limited than many believe.

A crisis in relations between the US and Iran – which has the potential to produce a military confrontation in the Middle East – is building rapidly in the expectation that President Donald Trump will withdraw the US from the Iran nuclear deal in just over two weeks’ time.

Mr Trump is demanding that Iran effectively renegotiate the terms of the agreement which traded the suspension of US economic sanctions for a stop to Iran’s nuclear programme.

The White House sounds as if it has already decided to exit the agreement, which Mr Trump persistently denounced before and after his election as “the worst deal in the world”.

But he has put forward no alternative to what was successfully negotiated by President Barack Obama in 2015 other than a series of demands with which Iran is unlikely to comply, and appear designed to put the blame for the US action on Iran.

US officials admit that Iran has so far abided by the terms of the 2015 accord.

A more openly confrontational posture by the US towards Iran would achieve very little, unless Washington replaces the attempt to achieve its ends by diplomacy with sustained military action. Iran is already on the winning side in the wars that have raged in Iraq since 2003 and in Syria since 2011.

It is closely allied to the Iraqi and Syrian governments and to reverse the balance of power in the region, the US would have revert to sustained military intervention on the scale of the Iraq War, something Mr Trump has always opposed.

Iran may have already decided that the deal cannot be saved. Iranian president Hassan Rouhani warned Mr Trump on Tuesday that the US must stay within its terms which Tehran signed with other great powers or face “severe consequences”.

Mr Rouhani said in a live broadcast on state television that: “I am telling those in the White House that if they do not live up to their commitments, the Iranian government will firmly react.”

The Iranian leader did not say what this reaction would be, but the Iranian foreign minister Mohammad Javad Zarif said at the weekend that it was “highly unlikely” that Iran would remain in the agreement – to which Russia, China, France, Germany and Britain are also signatories – if the US pulled out.

He added that Iran might immediately begin enriching uranium, but it would not develop a nuclear device.

European leaders are trying to save the deal which Mr Trump has denounced as full of “terrible flaws”, but this will prove difficult without radical concessions which Iran has rejected. These include stopping Iran’s ballistic missile programme, extending the terminal date of the agreement, and more intrusive inspections by nuclear inspectors.

No decision in Washington is final until it is announced by Mr Trump himself – and often not even then – but the promotion of officials with a record of hostility to the agreement suggests that it cannot be rescued. Mr Trump has said publicly that he sacked his secretary of state, Rex Tillerson, because he wanted to stay with the Iran agreement negotiated by President Obama.

His replacement, Mike Pompeo, is a long-term foe of the accord, once claiming that 2,000 bombing sorties would be enough to eliminate Iran’s nuclear capability. “This is not an insurmountable task for the coalition forces,” he said.

President Emanuel Macron is in Washington on a state visit, trying to save the agreement by making it more palatable to the White House. He will be followed in the US at the end of the week by the German chancellor Angela Merkel, while Theresa May will probably express her views by telephone.

All three leaders will try to reconcile Mr Trump to not leaving the accord and their arguments will revolve around supplementary sanctions and other measures targeting the Iranian ballistic missile programme and Iran’s allies abroad such as Hezbollah in Lebanon.

The European leaders’ mission may not be entirely hopeless: in confrontations over Syria and North Korea, Mr Trump’s belligerent rhetoric has been followed by more carefully calculated action.

His opening stance is normally bombastic and uncompromising in order to intimidate the other side into making concessions. It does not necessarily have to be taken at face value. But this periodic moderation may not come into play in the case of Iran, towards which he has been uncompromisingly hostile, claiming that it is the hidden power behind “terrorist” activity in the Middle East.

The White House is in a position to hurt Iran economically by re-imposing economic sanctions, not that these were ever really lifted after 2015, but US political options are more limited. It may talk about regime change in Tehran, but is not in a position to do much about it.

There is a further US weakness: the US, often prompted by Israel, and Saudi Arabia, has a track record of underestimating the extent to which Iran, as the largest Shia Muslim power, plays a leading role in a coalition of states – Iraq, Syria and Lebanon – because of the predominant influence of the Shia in these countries. It is very difficult to defeat Iran there – the northern tier of the Middle East – but it is in this region that the US has chosen over the years to try to roll back Iranian influence.

The balance of power between Iran and its enemies is going to be difficult to shift whatever Mr Trump decides about the fate of the Iran nuclear deal.