Zimbabwe's neighbors should close their borders in an attempt to bring down President Robert Mugabe, Botswana's foreign minister said Wednesday in the strongest call yet for action from Africa.The leaders should "tell Mugabe to his face, 'Look, now you are on your own, we are switching off, we are closing your borders,' and I don't think he would last. If no petrol went in for a week, he can't last," Skelemani said.