The threat of a strike by hundreds of thousands of health workers moved closer yesterday after a conference held by Unison, the largest public sector union, voted to ballot on industrial action unless the government improved its pay offer. Health workers have voted to reject a 2.5 per cent staged pay award, worth only 1.9 per in the current financial year. The conference unanimously agreed to ballot Unison's 450,000 National Health Service members on action "up to and including a strike" unless the offer was improved.

Unison said it would work with other NHS unions to secure a better deal, raising the prospect of wider action involving more than 1m health workers.