NHS nurses march during a strike, amid a dispute with the government over pay, in London, Britain December 20, 2022 (Reuters)

Nurses in Britain are prepared to strike until Christmas if they cannot reach a deal with the government on pay, the leader of the country's main nursing union said on Sunday.

Members of the Royal College of Nursing (RCN) would strike at the end of April and the beginning of May before holding a ballot on continuing the strike to the end of the year, union leader Pat Cullen said.

"If that ballot is successful it will mean further strike action right up until Christmas," Cullen told the BBC’s Sunday with Laura Kuenssberg program.

Members of the union rejected a government pay offer on Friday and immediately announced an escalation in strike action.

Hopes had been high that nurses in England would accept the five percent pay offer brokered by the RCN and the government in March. But after putting the offer to its members, the RCN said 54% turned it down.

RCN members will walk out for 48 hours from 8:00 pm (1900 GMT) on April 30, with the action extended to staff in emergency departments, intensive care, and cancer care units for the first time.

The refusal is a setback for the government, which had hoped for an end to the crippling health sector strike that has seen thousands of operations and appointments canceled.

'Hugely disappointing'

Hospital doctors below consultant level have this week been on a four-day strike demanding better pay and conditions.

Cullen said she had received a letter from Health Secretary Steve Barclay on Sunday morning after requesting talks with him about the pay offer last week.

RCN members walked out for the first time in the union's 108-year history late last year, joining a wave of public and private sector workers calling for pay rises as inflation soared.

The government said the RCN rejection of the pay offer was "hugely disappointing" and claimed it was "fair and generous".

As well as a five percent pay increase in the next financial year, the offer included a one-off bonus worth at least £1,250 ($1,510) per person.

Two other unions representing healthcare workers have yet to announce the results of their ballot on the offer.

Healthcare bosses say further strikes would have an impact on reducing already lengthy waiting lists for treatment, which UK Prime Minister Rishi Sunak has pledged to reduce.