For many decades the British royals have acted as one of the UK’s most potent instruments of “soft power” in promoting close relations with the ruling families of the United Arab Emirates, other Gulf states and the Hashemite Kingdom of Jordan.

However, revelations of the British family court judgments in the case involving the ruler of Dubai, Sheikh Mohammed bin Rashid al-Maktoum, his estranged wife Princess Haya of Jordan, their children and the abduction of two of the sheikh’s daughters by a previous marriage pose problems. Not solely for the British royal family, but for the Foreign Office too, as a total estrangement between the British royals and those of the UAE could jeopardise a vital British interest.

A mutual interest in breeding racehorses has made for a strong personal rapport between the Queen and the sheikh, who is vice-president and prime minister of the UAE. But the Queen, it was reported yesterday, will now avoid being photographed with him.

In this case, the personal is highly political. Along with Saudi Arabia, the UAE is a valued customer for British arms exports and related defence contracts. Since the 1980s, the purchases of British arms by these two Gulf states have been the mainstay of Britain’s arms industry. Without them, it is unlikely that BAE Systems could have maintained its production lines through the transition from the Tornado to the Eurofighter, for example, and Britain could have become more dependent on US-made equipment for its own armed forces.

What’s more, the relationship with the Emirates is considered a key target for a new trade agreement post-Brexit – as evidenced by Boris Johnson’s call last week to the Abu Dhabi crown prince Mohammed bin Zayed, the de facto ruler of the UAE. In effect, the UK needs the UAE more than ever.

It was not always thus. Before 1971, when the British formally withdrew their forces east of Suez, and the UAE, along with Britain’s other semi-protectorates in the Gulf, Bahrain and Qatar, gained full independence, the rulers of these states were subsidised by the British. After independence and nationalisation of the energy industries of all the Arab states and Iran, these states became cash rich. This meant that the primary goal of the British banking sector was to ensure their petrodollars were deposited in London. They succeeded.

Britain proved the preferred destination for Gulf investors, leading to Arab ownership of real estate and enterprises that benefited the British economy and gave their owners a growing influence in the UK. British exporters of consumer goods and infrastructure also gained lucrative contracts in the Gulf as these states developed their economies.

The presence of so many British nationals and enterprises in the Emirates is both an asset and, potentially, a liability

From a skeleton presence before 1971, in subsequent years the number of British expatriates operating businesses in the UAE burgeoned to many hundreds, and Dubai in particular became a popular tourist destination. As the former UAE ambassador to London Easa Saleh al-Gurg reflected in his memoir: “We had to recognise that although the British presence was no more, the British themselves were still very much with us.”

The British relationship with the UAE has therefore become one of mutual dependence and the presence of so many British nationals and enterprises in the Emirates is both an asset and, potentially, a liability in time of crisis.

Britain’s relationship with Jordan, and the links established between the British royals and the Hashemites, are also close, but of a different order. Jordan is not rich and, given the size of the national debt and lack of employment opportunities for its youthful population, the government there has looked to the Gulf Arabs for handouts. Since the invasion of Iraq in 2003 and latterly the long-running conflict in Syria, Jordan has given shelter to millions of refugees, rendering it doubly reliant on foreign aid.

Facebook Twitter Pinterest The missing princesses: sheikhas Shamsa and Latifa al-Maktoum. Composite. Composite: The Guardian/AP

Latterly, Donald Trump has shown scant regard for the threats to stability in Jordan exacerbated by his so-called “deal of the century” proposals for resolving the Israeli-Palestinian conflict. His plan envisages Israeli annexation of the Jordan Valley as well as other swathes of the West Bank captured by the Israelis from Jordan in 1967. If the Israelis go ahead unilaterally with such annexations, Jordan will suffer.

Police to review inquiry into 2000 disappearance of Dubai ruler's daughter Read more

Given this, the Jordanians will look to the British to be more sympathetic to their concerns. Yet they, as the British, can ill afford a falling out with the UAE. The fact that a British court has now ruled in favour of Princess Haya in a case against Sheikh Mohammed, and she and her children have sought safety in the UK, adds a new complication to the British government’s need to protect both its relations with the UAE and its interests in the stability of Jordan.

As it happens, Israel is another of the countries with which Britain is planning to forge a new trading relationship post-Brexit. The prospects of keeping on the right side of the Israelis if they fall out with the Jordanians and with the UAE if its rulers cannot be persuaded to take the British court’s judgment in their stride will not be easy. A further complication is that the FCO appears to have turned a blind eye to the abduction of one of Sheikh Mohammed’s daughters, Sheikha Shamsa, from the streets of Cambridge in 2000.

In the coming days, the case will be made that upholding the rule of law in Britain is vital for Britain’s reputation. Further, the FCO must be required to explain any cover up. But even if it does, making recompense will require the government to face some agonising choices. There’s plenty more than royal friendship at stake.

• Rosemary Hollis is a former Professor of Middle East policy studies at City University London