(Bloomberg) — U.K. health workers will strike in January and February as a dispute with the government over pay escalates, two labor unions announced.

Members of Unison will walk out for 12 hours on Jan. 29 and 24 hours on Feb. 25, the union said in a statement today. The planned action follows two four-hour strikes in October and November, and the January protest will coincide with a 48-hour strike by ambulance workers from the GMB union.

“Our members’ pay has been frozen or held down for the past five years and there is no end in sight,” said Christina McAnea, Unison’s head of health. “We now have no option but to escalate and plan for longer strikes. The anger among health workers has reached levels where they are now ready to walk out for 24 hours.”

Public-sector pay has been held down by the coalition government elected in 2010 as part of Prime Minister David Cameron’s program to reduce Britain’s budget deficit. On average, health workers have lost about 10 percent of the value of their pay since 2010, McAnea said.

There will also be a program of other action, including a “work to rule” between the two strikes, Unison said. That means staff will only work their contracted hours, take full breaks and not do unpaid overtime.

See also: Plans in showdown against high-cost drugs.

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