(updates with new Brown quote)
By Michael Holden
LONDON, Oct 22 (Reuters) - Thousands of postal workers at state-owned Royal Mail walked out on Thursday, starting a 48-hour nationwide strike and blaming bosses and the government for failing to prevent the action.
Members of the Communication Workers Union (CWU) are taking the action in a long-running dispute over pay, jobs and modernisation plans which the company and ministers say are essential if Royal Mail is to survive.
About 42,000 mail centre staff and drivers walked out in the morning and 78,000 delivery and collection staff will strike on Friday which is expected to completely disrupt mail deliveries.
"They are not modernising the service, they are planning huge cuts," CWU Deputy General Secretary Dave Ward told BBC television. "What we want is an opportunity to resolve this. We don't want to damage customers -- we have no alternative."
Prime Minister Gordon Brown said the strikes would be self-defeating, leading to more job losses. He said the government would do everything it could to resolve the dispute.
"It's essential that everybody gets round the table. This strike is solvable, and I believe that management and the workforce can reach a solution to this and we should do this as quickly as possible," he told reporters.
The action is likely to embarrass Brown's Labour government. The opposition Conservatives, well ahead in opinion polls with an election due by mid-2010, are already attempting to make political mileage out of the dispute.
The government wants to sell up to 30 percent of the company to make it more competitive, but shelved those plans earlier this year due to adverse market conditions and strong opposition from workers and Labour politicians.
Royal Mail's business has declined by some 10 percent annually in recent years as customers switch to the Internet or more specialised services.
The CWU blamed Royal Mail bosses and Business Secretary Lord Mandelson for the breakdown in talks, saying they sought revenge for the staff's opposition to privatisation.
Operations director Paul Tolhurst said Royal Mail wanted the union to sign up to agreements apparently reached this week.
"We are waiting for a call from the CWU -- our phones lines are open, our doors are open," he told BBC radio. "We will meet them as soon as we can. What we've got to get away from is these damaging strikes."
Mandelson says that if it does not embrace change, the company faces "terminal decline", but Conservative leader David Cameron said the government's failure to go ahead with its part-privatisation plans had galvanised union militancy.
The CWU said it would announce further strike dates next week while Royal Mail has said it would hire 30,000 temporary staff to help cope with the expected seasonal backlog. (Additional reporting by Matt Falloon)