Saudi Arabia's King Salman will not attend a Camp David summit of US and allied Arab leaders, his foreign minister, Adel al-Jubeir, said, raising questions about relations between Riyadh and Washington.

In a statement on Sunday, Jubeir said Thursday's summit coincides with a humanitarian ceasefire in the conflict in Yemen, where a coalition of Arab nations is fighting Houthi rebels.

He said Crown Prince Mohammed bin Nayef, who is also interior minister, would lead the Saudi delegation and the king's son, Deputy Crown Prince Mohammed bin Salman, who is defence minister, will also attend.

President Barack Obama had planned to meet Salman one-on-one a day before the gathering of leaders at the presidential retreat.

Yemen war dominates GCC summit in Riyadh

The Kingdom of Bahrain said separately that its delegation would be headed by the country's crown prince, Salman bin Hamad Al Khalifa

The sultan of Oman, Qaboos bin Said, is among those staying away. The sultanate will be represented instead by the deputy prime minister, Sayyid Fahd bin Mahmoud Al Said, and other officials, the country's official news agency announced.

Health issues will also keep the president of the United Arab Emirates, Sheikh Khalifa bin Zayed Al Nahyan, from attending. He suffered a stroke in January last year and has not been seen publicly since.

The influential Abu Dhabi crown prince, Sheikh Mohammed bin Zayed Al Nahyan, will lead the Emirati delegation.

Among those who will be at the summit is the Kuwaiti emir, Sabah Al Ahmad Al Sabah. He arrived at Andrews Air Force Base on Monday, the official Kuwait News Agency reported.

Also, Qatar's emir, Sheikh Tamim bin Hamad Al Thani, is scheduled to depart Monday to take part in the meeting.

'No substantial disagreement'

The White House said it did not take his decision to skip the summit as a sign of any substantial disagreement with the US, but some commentators called the king's cancellation a snub.

The New York Times said: "The decision appeared to be a signal of Saudi Arabia's continued displeasure with the Obama administration over United States relations with Iran, its rising regional adversary."

Arab allies feel threatened by Iran's rising influence and worry a nuclear pact taking shape with the US, Iran and other nations may embolden Tehran to intrude more aggressively in countries of the region.

King Salman, who took power in January after his brother King Abdullah died, has not travelled abroad since his ascension to the throne.

At the Camp David summit, leaders of Gulf nations will be looking for assurance that Obama has their support when comes to the fighting armed groups in Syria, Iraq and Yemen.