nic robertson, cnn, saudi/yemen border. >> iraqi prime minister's first visit will focus on the battle against isis. al abadi to meet president obama in the white housen the coming hoursen fact. mr. abadi toemd reporters he'll ask for more. he wan isis controls about 1/3 of iraq. >> isis withdrew from tikrit recently. but the fighting is far from over. awar damon reports the president's trip to washington, comes as the country copes with tax on a number of friend. isis is tryinging back and hard. this video posted by isis shows thick plumes of black smoke rising from the oil refinery. the refinery had been under government control for months.