The head of Libya’s rebel government says the only way it can succeed is if the international community frees all of his country's assets frozen during Colonel Moammar Gadhafi's reign. Libya’s Transitional National Council chief Mahmud Jabril on Friday said the opposition needs the money in order to pay the salaries of civil servants and maintain services. He was speaking in Istanbul, where he had attended a meeting of diplomats a day earlier focused on the Libyan crisis. On Friday, the United States said it will soon release 1.5 billion dollars in frozen Libyan assets to the country's opposition-run council for urgent humanitarian aid. The United Nations Security Council approved the funds' release after US and South Africa reached a deal, designating where the funds would go. Meanwhile, rebels' interim government has started operating in the capital, Tripoli, moving its base from Benghazi, where the revolution to topple Colonel Moammar Gadhafi began months ago. The move comes as some opposition fighters poured into Tripoli to help combat the remnants of pro-Gadhafi forces while others advanced toward the Libyan leader's hometown of Sirte, where his loyalists have been massing for a showdown. Separately, the International Organization for Migration (IOM) announced it had sent another ship to rescue foreigners from Tripoli and deliver some 50 humanitarian workers. A IOM charter ship left the city with 263 migrants on board last evening. Fierce gun battles rang out in the capital Tripoli on Thursday as Mr. Gadhafi used a short audio broadcast to rally his supporters and denounce foreign countries for their involvement in the conflict.