RJB Mining, the coal company seeking more than £70 million in Government aid said that it may have to close two collieries after reporting heavy losses.
The group, which controls about 60% of British coal mining, made a loss after tax of £130 million in the year to December 31, compared with a £40.1 million profit in 1998.
The company are now threatening to close Ellington colliery in Northumberland and Clipsone colliery in Notinghamshire with the total loss of 520 jobs.
RJB said last year's losses included one-off charges of £141 million. Of that, £15.8 million came from redundancy and pit closure costs, with the rest from a revaluation of its colliery assets.
Chairman John Robinson had held back publication of the figures in the hope of securing the state aid.
He said: "We are disappointed that this decision has not been made by now."
The company has offered a guarantee to keep open all of its 13 deep mines, including Ellington colliery, the last pit in north east England, if its demands for state aid are met in full.
Otherwise, the group will carry out its threat made last year to close the pit.
The Clipstone colliery in Nottinghamshire would also be saved if the Government aid came through, RJB said.
Sales by the troubled mining company for 1999 were down at £699.2 million against £822.5 million the year before.
Stripping out the exceptional costs, RJB made a pre-tax profit of £11 million last year compared with £50 million in 1998.
The company has come under pressure from cheap foreign coal suppliers and the increasing use of gas-fired power stations.
Total use of coal in generators fell by 17% in Britain last year alone.
Chief executive Richard Budge warned against Britain becoming solely dependent on gas and nuclear power and added that RJB had made a "robust" case for aid to the Department of Trade and Industry.
"It would be ridiculous to be losing UK jobs when European governments are subsidising theirs," he said.
He claimed his mines ran at a third of the cost of German collieries and a fifth of those in Italy, both of which received substantial government subsidies.
While disappointed at not having received a decision from the DTI, he said: "These are very difficult choices for the Government to make.
"They need to be well thought out, but we are confident they are seriously looking at our proposals."
Coal prices, which hit record lows last year, were starting to increase.
Shareholders will pick up a total dividend of 7.5p-a-share compared with 7p last year.