President Barack Obama visited Saudi Arabia on Tuesday to pay his respects days after the death of King Abdullah. He trip was also a chance to patch up relations with the oil-rich kingdom which is a key American ally in the Middle East.

Deputy National Security Advisor Ben Rhodes told reporters Obama wanted to forge the same kind of “close relationship” with Saudi Arabia’s new king, Salman bin Abdulaziz Al Saud, as he had with his older brother and predecessor.

Abdullah died on Friday after a decade on the throne. He had ruled Saudi Arabia as regent since 1996 after his predecessor, King Fahd, suffered a stroke.

Officials said Obama and the new king discussed Iran’s nuclear ambitions, the fight against Islamic State militants in Iraq and Syria as well as the situation in Yemen where President Abd Rabbuh Mansur al-Hadi stepped down on Thursday.

Hadi was backed by both Saudi Arabia and the United States. His resignation, forced by Shia Houthi rebels from the north of Yemen, is likely to have exacerbated Saudi Arabia’s apprehension about Iran’s spreading influence in the region.

The two powers are locked in a struggle for hegemony in the Middle East. The conflict is informed by contrasting religious views. The Saudi monarchy sees itself as the guardian of Islam and conservative Sunni hierarchy; Iran’s rulers consider themselves the vanguard of an Islamic revolution.

The struggle has played out across the region. In Iraq, Saudi Arabia resisted Iran’s growing influence in Baghdad during the prime ministership of Nouri al-Maliki, a Shia Muslim who spent decades in exile in Iran when Saddam Hussein was in power. In Syria, they support opposing sides in a civil war: Iran backs the minority regime of President Bashar al-Assad while Saudi Arabia, working with the United States, supports the largely Sunni opposition.

America’s rapprochement with Iran and Obama’s eagerness to do a deal with the country before it develops nuclear weapons has alarmed the Saudis.

They were previously dismayed when Obama withdrew his government’s support from Egyptian strongman Hosni Mubarak in 2011 and later refused to deepen America’s involvement in the Syrian conflict.

To show how crucial the Saudi alliance nevertheless is for the United States, the president cut short a visit to India to lead a high-ranking delegation to Riyadh.

Secretary of State John Kerry, National Security Advisor Susan Rice and the director of the CIA, John Brennan, accompanied Obama on his visit. So did former members of the George W. Bush Administration, including former secretary of state Condoleezza Rice, and members of Congress.

Previous disagreements, over America’s recognition of Israel in 1948 and the 2003 Iraq War, did not lead to a serious breach in bilateral relations. Saudi Arabia depends on the United States for its security and no other great power is able or willing to take its place.