The White House has said "more will be required" to ensure the viability of General Motors and Chrysler after the companies submitted restructuring plans.

Spokesman Robert Gibbs said in a statement: "We appreciate the effort that these companies and their stakeholders have made, and the president's team will be reviewing these reports closely in the days ahead.

"It is clear that going forward, more will be required from everyone involved - creditors, suppliers, dealers, labour and auto executives themselves - to ensure the viability of these companies," he added.