US President Barack Obama arrived in Saudi Arabia on Wednesday in what is expected to be his final visit to the kingdom before he leaves office this year. He will meet with Saudi King Salman, before a Gulf Cooperation Council summit of leaders from Saudi Arabia, Bahrain, Kuwait, the UAE, Qatar and Oman on Thursday. The president is set to consult Washington's Gulf allies on the crises in Yemen and Syria in particular. The president is expected to push Saudi Arabia, the world's top oil exporter and biggest buyer of US-made arms, and other Gulf allies for greater cooperation and military backing in the fight against ISIS, which controls large areas of Iraq and Syria. While the two powers have warm ties that stretch back for seven decades, Saudi Arabia has been frustrated with Obama on a number of issues, including the US-led Iranian nuclear deal. After concluding his Saudi visit, Obama will then travel to Britain and Germany. Prior to Obama's arrival, US defense chief Ashton Carter met with GCC defense ministers.