The High Court in London has reserved judgement until early next week on whether Unite can proceed with strike action at the construction giant Balfour Beatty.
Unite has called on the company to re-open negotiations immediately during the pause before Mr Justice Eady issues his ruling.
The company had sought an injunction to prevent the union calling strike action against its threat to impose new contracts on up to 1,800 electricians, plumbers and other engineers.
In a ballot result announced last week, 67% voted for strike action. Unite had agreed not to nominate any dates for action pending the outcome of the case.
Unite says the contracts – which Balfour and seven other companies in the self-appointed BESNA group wish to impose on sparks by April 2012 – will result in extensive deskilling, undermine safety levels and cut pay and allowances by up to 35%.
Balfour Beatty’s case for an injunction is understood to have centred on a claim that Unite had not maintained accurate membership lists under current anti-union legislation.
Unite national officer Bernard McAulay said: “Balfour Beatty’s failure to recognise the strength of feeling among skilled workers is prolonging a long and bitter dispute. We will not bow down to bully boy tactics either in the workplace or the court room.