The Bush White House still needs assurances Detroit's automakers would survive after a $15bn federal bailout, it emerged last night.

President George W Bush has questioned the ability of the companies to continue operations, which prompted a meeting yesterday afternoon between his White House aides and Democratic party congressional staff who sought to address the administration's concerns with a counter proposal, Reuters reported.

The Bush administration reportedly hopes for a deal but insists that the companies be commercially viable, Reuters said.

"Viability means that all aspects of the companies need to be re-examined to make sure that they can survive in the long term," Bush reportedly said in an interview with ABC News' 'Nightline'.

Forced changes in management were not in the latest plan though some senate and house leaders have said GM CEO Rick Wagoner should step down.

House speaker Nancy Pelosi told Reuters that federal money would only be handed over if management, labour, bondholders, dealers and others make serious concessions.

"Everyone's taking a hair cut," she said.

The Democrats have proposed a 31 March deadline for the automakers to submit detailed plans to cut costs and further overhaul their businesses.

By then, new president Obama will be in power. He has expressed more sympathy for the automakers' plight than Bush but has indicated they must restructure to match market conditions.

Lawmakers have questioned whether Chrysler can keep its independence, according to Reuters. Chrysler CEO Bob Nardelli told employees on Monday the company can survive, although management has said alliances are crucial to its future.

It emerged today a planned alliance with Chery to produce small cars has ended, however.

There has also been debate over whether Chrysler, majority-owned by private equity investor Cerberus should get federal help at all as the parent firm has access to funds of its own.

Chrysler told Reuters it plans to complete its restructuring "in an orderly fashion," if it receives the loans it has requested.

GM said in a statement: "We will abide by the conditions proposed in the bill and will continue our restructuring with great urgency.

"We have put together a restructuring plan that will deliver a stronger, sustainable GM in a quicker time frame and without the negative market consequences that could result from bankruptcy."

Reuters said the Democrats' plan would grant the government the right to acquire preferred shares, or the economic equivalent, equal to 20% of the amount loaned to each automaker.

Other conditions include no bonuses or 'golden parachutes' for top executives are permitted, the sale of company planes and the ending of lawsuits against California's law limiting greenhouse gas emissions, which would boost fuel efficiency.

In an amazing display of humility, GM published an advertisement in a leading trade newspaper yesterday acknowledging it had "disappointed" and sometimes even "betrayed" American consumers by letting "our quality fall below industry standards and our designs become lacklustre".

The House speaker, Nancy Pelosi, told the New York Times she hoped that Bush's appointee - or 'car czar', as the position has come to be known - would not need to be replaced by president-elect Barack Obama, raising the prospect that the outgoing and incoming administrations would cooperate in selecting someone.

The 'car czar' would distribute the short-term emergency loans to General Motors and Chrysler, which are at risk of financial collapse, and would directly supervise reorganisation the auto manufacturers have agreed to carry out in exchange for the government aid, the paper added.

Ford last night said it would not seek short-term federal aid, denying that it faced the same "near-term liquidity issue" as GM and Chrysler, according to the NYT.

Officials were optimistic they would agree a deal and that Congress would vote on the package this week, the paper added.