Roy Lynk, who has been president of the breakaway union since the strike, is succeeded by Neil Greatrex, 54, who has taken a far more sceptical line about Conservative policies.
Mr Greatrex, who also worked during the strike, has opposed the UDM's participation in a consortium formed to bid for pits when the industry is privatised.
In the eyes of the UDM membership, Mr Lynk's flirtation with the Government came dramatically unstuck when Michael Heseltine, President of the Board of Trade, announced his pits closure programme. At the height of the controversy Mr Lynk staged a sit-in protest at Silverhill colliery near Mansfield, one of the collieries to be axed. He said then that he felt betrayed and that his position had become untenable because he had been treated with contempt by the Government and British Coal. His harsher critics remarked that if he had not gone down the pit voluntarily, members would have thrown him down.
He will remain as the non-TUC union's national secretary, but his influence will be impaired by his defeat. Two years ago Mr Greatrex lost by 106 votes in a ballot for the presidency. This time he won with a majority of 740.
While staging his 'stay-down' protest Mr Lynk said that he would step down from the presidency. After he returned to the surface, to a hero's welcome from his supporters, he had a change of mind and decided to stand against Mr Greatrex and a third candidate, Adrian Moorhouse, UDM branch secretary at the Thoresby colliery in Nottinghamshire.
Mr Lynk said in a statement yesterday: 'I have no doubt that the recent announcements by British Coal and the Government on the future of the industry damaged my credibility with the membership. But the future of this industry still hangs in the balance and I shall continue to vigorously fight the closure plans in every way that I can.'
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