A pay strike planned by thousands of college support staff next week could be halted today by a threat of legal action from their employers.
Unison, the country's biggest trade union, said it had received a letter from employers warning they were seeking an injunction to prevent a strike next Tuesday by up to 20,000 clerical, secretarial and administrative employees in colleges throughout England.
The union said it was being challenged on the legal provision to furnish employers with details of who is taking industrial action.
The workers are set to go on strike in protest at a 2.3% pay offer.
Christina McAnea, the union's national officer, accused the employers of resorting to "crude, bully boy tactics" to try to avert the strike. "We have been trying to negotiate with the employers since last July," she said.
"We received a letter out of the blue. The employers are obviously incapable of negotiating with us. We will be taking legal advice to try to resist this."
Unison said the employers were threatening to take legal action today.
College lecturers are also due to strike next Tuesday over pay.