A strike by teachers at sixth form colleges in England will go ahead today following a High Court ruling.
The National Union of Teachers (NUT) is to stage a one day walkout over funding cuts.
The Government had sought a court injunction to stop the strike, arguing it was politically motivated.
But Mr Justice Kerr refused to grant the Secretary of State for Education, Nicky Morgan, an urgent declaration that it was unlawful.
Clive Sheldon QC, for the Secretary of State, said the action was unlawful because it was not in furtherance of a trade dispute as it was not predominantly about terms and conditions of employment.
Instead it was about funding cuts and part of the union's political campaign Save Our Colleges, said the Government's counsel.
The judge said the likely outcome at any trial of the issue was that the NUT's strategy was to protect terms and conditions by shoring up the sixth form college sector - rather than shoring it up as an end itself.
The NUT's members' main concern was their perception that, if the colleges died, their jobs died with them.
In last month's ballot, 86% of members at the 92 colleges in England voted in favour of action on a 44% turnout.