King Abdullah meets President Barack Obama Friday as Mistrust fuelled by differences over Iran and Syria overshadows a decades-long Saudi-US alliance. Saudi Arabia has strong reservations about attempts by Washington and other major powers to negotiate a deal with Iran on its nuclear programme, and disappointment over Obama's 11th-hour decision last year **t to take military action against the Syrian regime over chemical ******* attacks. Saudi-US relations, dating back seven decades, are "tense due to Washington's stances" on the Middle East, especially Iran, said Saudi analyst Abdel Aziz al-Sagr, who heads the Gulf Research Centre.