Miners at Kellingley Colliery fear the general election result could be the ‘final nail in the coffin’ for the pit.
The site is due to close by the end of the year with the loss of 700 jobs after the government rejected a £338m state aid bid to extend its life until 2018.
Members of the National Union of Mineworkers (NUM) have written to Prime Minister David Cameron after he said the Conservatives would “represent working people” following their general election win earlier this month.
Keith Hartshorne, NUM delegate at Kellingley, said: “We had met Labour leader Ed Miliband and he had promised us that immediately following the election he would set up a committee at the future of the country’s remaining three pits.
“Obviously after such a crushing blow for Labour we quickly realised that was never going to happen. But after he won the election, David Cameron said the Tories would be the party of the working people so we have written to him asking him to come good on his promise and help the working people at Kellingley Colliery.
“The letter is more out of despair than hope and, although we have said it before, I honestly think the election really is the final nail in the coffin for Kellingley.
“We’re not daft. We know that the cost of the pit is mounting up with every day that goes by but we also know that the cost of saving the pit when they should have done was only £20m.”
Pontefract and Castleford MP Yvette Cooper said she would continue to work with miners at the pit to help secure redundancy packages and retraining.
Ms Cooper said: “Despite the devastating blow that the election result has delivered, I’ll still work with the miners and those involved with the pit to try and help them wherever I can.”
Mr Cameron’s office has written back to the NUM and said it was considering the contents of the letter before responding.