General Motors, which opened contract talks with the United Auto Workers on Thursday, said the $US13 billion it raised through a recent debt offering would only be paid into its underfunded US pension plans after it reaches a new contract with the union, according to Reuters. The news agency said that withholding the money, which GM raised through a massive bond sale last month, could be seen as a strike contingency measure as GM heads into likely difficult talks toward a new labour agreement this autumn.