NEW : British government says use of its assets would be theft . Rebels claim they have retaken southern city . The Libya considers seizing Moreno-Ocampo funds to help Misrata 's people . Congress suspends ships after Misrata is shelled .
NEW : Libyan government says use of its assets would be theft . Rebels claim they have retaken southern city . The U.S. considers seizing Gadhafi funds to help Libya 's people . The International Organization for Migration suspends ships after Misrata is shelled .