The Las Vegas-based casino operator, controlled by billionaire Sheldon Adelson, is also seeking amendments to its Macau bank loan, including covenant relief and permission to issue as much as $US1.5 billion ($A1.8 billion) in new debt, said the sources. Las Vegas Sands is seeking funds to restart work on its $US12 billion, 20,000-room complex of hotels and casinos on Macau's Cotai strip. Construction stopped last year amid near-frozen credit markets, dwindling revenue and the risk of defaulting on some loans.