Reuters : President Barack Obama plans to travel to Saudi Arabia in March on a mission to smooth tensions with Washington’s main Arab ally over US policy on Iran’s nuclear program and the civil war in Syria, a newspaper reported. Obama is preparing to meet with King Abdullah for a summit, the Wall Street Journal reported on Friday, citing unnamed Arab officials briefed on the meetings. “This is about a deteriorating relationship” and declining trust, said a senior Arab official in discussing the need for the summit, which was pulled together in recent days, the newspaper reported. A White House spokeswoman declined to comment. The United States and Saudi Arabia have been allies since the kingdom was formed in 1932, giving Riyadh a powerful military protector and Washington secure oil supplies. Washington’s relationship with the Saudis was crucial as the region faced changes and challenges from the transition in Egypt to civil war in Syria. But relations have been tested on a number of fronts. Members of Saudi Arabia’s ruling family threatened a rift with the United States to protest perceived American inaction over Syria’s civil war, which has killed more than 100,000 people, as well as the recent US outreach with Iran.