More than 650 postal workers at Preston's mail centre have taken part in a national strike over pay, working conditions and pensions.
A picket line was formed outside the centre on Pittman Way, Fulwood on Thursday morning as part of the first day of nationwide action in a dispute over pay, working conditions and pensions.
Officials from the North Lancashire and Cumbria branch of the Communication Workers' Union (CWU), which includes Preston, said the action was supported by 95% of the workforce at the centre.
Barry Bowes, assistant branch secretary, said the support came despite a concerted 'no' vote campaign from management.
He said: "Nationally, 67% of the membership voted for industrial action despite the recession and a concerted effort from management.
"Here we had letters sent home to workers, team huddles in the morning, all designed to press for a 'no' vote and yet the vast majority of people still voted for this action.
"This picket is only here because people expect us to be here and that is because there is no-one left in the mail centre except management which are doing deliveries."
On Friday, 78,000 delivery and collection workers across the UK will walk out.
Business Secretary Lord Mandelson urged the unions and Royal Mail to continue talking until the deadlock was broken and raised the prospect that the conciliation service Acas could become involved.
Speaking on Thursday, he said: "I don't think trading insults in this situation helps resolve the dispute.
"Politicising or dramatising it is useless, people need to focus on what issues are dividing them."
Nationally, up to 42,000 mail centre staff and network drivers launched a 24-hour strike on Thursday, while 78,000 delivery and collection workers will walk out on Friday.
The CWU is set to announce further strikes after hopes of reaching a last-minute deal collapsed, leading to bitter recriminations.
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