By Humeyra Pamuk
ABU DHABI (Reuters) -President Joe Biden sent a high-powered U.S. delegation to the United Arab Emirates on Monday to offer condolences after the death of its ruler, in an apparent bid to repair frayed ties with Gulf Arab allies.
Washington's desire to improve relations with Gulf monarchies has become more urgent following Russia's invasion of Ukraine, which highlighted the relevance of Gulf oil producers as Europe looks to cut its energy dependence on Russia.
Gulf states have so far refused to take sides in the Ukraine conflict. OPEC heavyweights Saudi Arabia and the UAE have also resisted calls to hike output to help tame crude prices that have aggravated inflation worldwide.
World leaders have been visiting Abu Dhabi to pay respects to new leader Sheikh Mohammed bin Zayed on the death of his half-brother. Saudi Crown Prince Mohammed bin Salman headed to the UAE on Monday to offer condolences, state media reported.
UAE's Foreign Minister Sheikh Abdullah bin Zayed told U.S. Secretary of State Antony Blinken over a business dinner in Abu Dhabi on Monday that his country under the leadership of Sheikh Mohammed looked forward to strengthening strategic relations with the United states, state news agency WAM reported.
U.S. Vice President Kamala Harris spent about three hours in the Emirati capital, heading a delegation that included nearly all of Biden's top national security aides, from the secretaries of state and defense and the head of the Central Intelligence Agency to high-ranking White House officials.
The make-up of the delegation reflected Washington's desire to show its commitment to the region, senior U.S. officials say.
Harris planned to emphasize the intent to deepen ties across areas ranging from security and climate to space, energy and commerce, they added.
Reporters traveling with Harris asked if she discussed oil with Sheikh Mohammed, but she did not answer.
"This is a major charm offensive on the part of the Biden administration to repair relations," said Omer Taspinar, a policy expert at the Brookings Institution think tank.
The Middle East had not been a priority for the Biden administration, whose primary focus had been tackling the China challenge. U.S. foreign policy has been dominated since February by the Ukraine conflict.
"The seniority and size of the U.S. delegation is a very telling signal and will be meaningful to Sheikh Mohammed and the UAE leadership," said a source familiar with Emirati thinking.
The UAE and Saudi Arabia both hold grudges against the Biden administration.
Biden has so far refused to deal directly with Saudi Crown Prince Mohammed as de facto ruler of the kingdom.
The Emiratis were frustrated by what they saw as lack of strong U.S. support in the aftermath of missile attacks in January by Yemen's Iran-aligned Houthis on Abu Dhabi.
Reuters has reported that Biden upset Sheikh Mohammed by not calling swiftly after the attacks and not responding more forcefully.
"There is an attempt to put things back on track after UAE frustration with the United States by the absence of high-level visits in the aftermath of Houthi attacks," Taspinar added.
Gulf states have chafed at perceived declining U.S. commitment to their security in the face of Iran's missile programme and network of regional proxies.
The UAE is at the same time engaging with Tehran to contain tension. Iran's foreign minister was due in Abu Dhabi on Monday.
Abu Dhabi and Riyadh have been frustrated by conditions on U.S. weapons sales. In December, the UAE said it would suspend talks on purchases of U.S.-made F-35 fighter jets because of conditions related to the sale.
The UAE says the United States remains a strategic partner even as the UAE deepens ties with China and Russia.
"There is progress, (but also) more to do. The UAE wants a closer and more clearly defined relationship with the U.S.," said the source familiar with Emirati thinking.