Vauxhall and Opel have withdrawn applications for European government funding aid, citing long delays in reaching agreements as a source of frustration.
In a statement, the GM brands said that their request for £1.5 billion in aid had been dropped, but added that the money was still needed. It said it would fund the restructuring itself instead.
"GM's recently improved financial strength has been a catalyst for making this decision," the carmaker said in a statement, adding that it expected to return to profitability "shortly".
GM Europe president Nick Reilly said: "We cannot afford to have uncertain funding plans and new time-consuming complex negotiations at this time when we need to keep investing in new products and technologies."
Germany has rejected a request for state aid, while the UK government is reviewing £275 of promised loan guarantees.