"I feel very sorry because it's a very important company and they've been super competitive in F1, but it's something we've been expecting with some of the big manufacturers," added Mosley.
"It's not possible that they go on spending the sort of money they're spending with the industry as a whole in so much trouble.
"All of these companies have problems, they're shutting factories, putting people on short-term contracts and even in most cases depending on taxpayers money, through things like scrapping schemes.
"So it doesn't really fit that they spend a great deal on F1 so we still need to get the cost down to show they're not wasting money."
Mosley's row with the chiefs of many leading F1 teams over a planned budgetary cap have been one of the main talking points of the sport this year, after a very public row between the two sides.
With somebody whose core business is not F1, there's always the possibility they're going to leave
And he said as the reality of the situation became more clear, he was happy to be more direct in his approach to get things done.
"Team principals who run the teams don't want their budgets cut but we're now going over their heads to the chief execs of these big companies saying 'you've got to back us up in efforts to get costs down', - and I think all the indications are that this will happen," he stated.
"I don't know that we'll get a budgetary cap, but we may get a significant reduction in expenditure.
"Teams are making efforts to reduce but we don't think they've gone far enough or fast enough."
Mosley said he had no reason to expect any more teams to bail out on next year - but he was not being complacent.
"There are rumours, but there are always rumours, so we don't pay attention until we get concrete information," he said.
"All the manufacturers to some extent have to be kept an eye on, as they've all come in and out (of the competition) on more than one occasion.
"You always have a worry about a manufacturer as it's not their core business.
"Somebody like BMW, their business is making cars, whereas for Williams, F1 is their business.
"With somebody whose core business is not F1, there's always the possibility they're going to leave."
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