India's Tata group may have to pump in at least $1 billion (£670.5 million) to revive the premium Jaguar and Land Rover brands it bought from Ford earlier this year.

That would come on top of any bailout from the UK government for the ailing car firm.

Jaguar Land Rover has about 16,000 employees in the UK and spends £400 million a year on research and development and £2.5 billion on suppliers. Its sales from June to September slipped 11.8% from the same time last year.

Tata is looking at a range of options to raise cash for the British brands, according to reports in India.

"We will do everything in our ability to resource all our operations," a Tata Motors' spokesman said.

Tata Motors paid $2.3 billion to buy Jaguar Land Rover from Ford, just as global auto sales began collapsing.

Tata Motors is already injecting "tens of millions of pounds" into Jaguar Land Rover to prevent an immediate cashflow crisis but much more may be needed.

"The company is spending whatever is required to the best of its abilities," said Tata Motors' Debasis Ray.

The British government has been tight-lipped about any prospect of taxpayer help for the carmaker.

Tony Woodley, joint general secretary of Unite, the biggest trades union, said Jaguar Land Rover was expected to receive support from the government before Christmas.