King Salman has decided to ditch plans to travel to the United States and will not be able to attend the Gulf Arab summit hosted by President Barack Obama at Camp David, the Wall Street Journal reports.

Before this decision, however, the White House had been optimistic King Salman would be able to visit to "resume consultations on a wide range of regional and bilateral issues," said White House spokesperson Eric Schultz Friday in the Wall Street Journal.

But by Sunday, the king said he would not be proceeding with his travels to Washington and will be sending interior minister and Crown Prince, Prince Mohammed bin Nayef, in his place. The summit with Obama will reportedly overlap a scheduled ceasefire agreement with Yemen, according to the Daily Star. Saudi Arabia is expected to start its humanitarian relief center in the region during this ceasefire.

Officials from Saudi Arabia, however, believe that the king had been disappointed with the United States over a disagreement with Obama's offer for its Arab allies in matters relating to Iran, which has been building its nuclear power. An unnamed source apparently said that Saudi Arabia is asking for the same offer the U.S. provided Israel in terms of defense system and military access to equipment, machines and satellites, according to a report from Fox News.

But the White House has downplayed this speculation.

"We look forward to the attendance of Crown Prince Mohammed bin Nayef, with whom the president has met on several occasions, including in the Oval Office in December 2014 and January 2013," said the spokesperson for the National Security Council, Bernadette Meehan, via the Wall Street Journal.

The summit, organized by the Obama administration, is expected to be attended by six nations under the Gulf Cooperation Council, such as Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and United Arab Emirates. The leaders of these countries will be discussing Middle East policies with the U.S., particularly in its engagement with Iran.