Britons should leave Mali and those considering visiting the West African nation should stay away, Britain's foreign ministry said on Saturday. A coup in Mali was triggered last week by anger at President Amadou Toumani Toure's handling of a rebellion in the north of the country which has continued to gain momentum since the military takeover. “We advise against all travel to Mali,” the Foreign and Commonwealth Office said. “Given ongoing instability in the country, and now that the airport has re-opened, you should leave if you have no pressing need to remain.” Meanwhile, rebels in pick-up trucks loaded with heavy arms attacked the northern Mali town of Gao Saturday, capitalizing on the chaos caused by last week's military coup to make further gains. The attack came a day after the rebels seized the town of Kidal which, along with Gao and the historic trading city of Timbuktu, is one of the three main towns of Mali's north. A Reuters reporter saw the rebels entering the town and hoisting the flag of Azawad, the desert territory bigger than France that they want to make their homeland, before pulling back after meeting resistance. But Gao, a town of 90,000 people, has the largest garrison in the north, and army resistance was stronger than in Kidal. Government forces held onto the town center and in the afternoon rebel units began to pull back, their base in a captured fire station on Gao's outskirts coming under attack from army helicopters and heavy weapons.