London, The UK is bracing for more strikes after a summer of walkouts by staff in various sectors including public transport, container port operation and postal delivery, due to long-running disputes over pay.

More than 300,000 members of the trade union Royal College of Nursing (RCN) received ballot papers from Thursday, launching the union's biggest strike ballot in its 106-year history, reports Xinhua news agency.

"We are understaffed, undervalued and underpaid. For years our profession has been pushed to the edge, and now patient safety is paying the price. We can't stand by and watch our colleagues and patients suffer anymore," said the union's general secretary Pat Cullen.

"We're campaigning for a pay rise of 5 percent above inflation to overcome a decade of real-term pay cuts, support nursing staff through the cost-of-living crisis and recognize their critical skills," the RCN said.

Unite, one of the largest trade unions in the UK, on Wednesday announced more than 300 offshore drilling and contract maintenance workers had backed strike action after rejecting a 5 per cent pay rise offer.

The walkouts will involve a series of stoppages from October to the end of this year.

"The offer on the table is a substantial real-term pay cut" when taking into account the persistently high inflation rate in the UK, Unite general secretary Sharon Graham said.

The UK's consumer price index (CPI) rose by 9.9 per cent in the 12 months to August. This was down from a 40-year high of 10.1 per cent in July, but still an elevated level.

Amid the worsening cost-of-living crisis, a new round of industrial actions started at the end of September at key UK container ports in Felixstowe and Liverpool.

The walkouts mean over 60 per cent of the UK's container port capacity will be affected, Unite said.

Royal Mail workers have also decided to stage a further 19 industrial actions from mid-October to early December, including the Black Friday week, in a long-running dispute over pay and conditions.

Meanwhile, staff at Network Rail, the owner and infrastructure manager of most of the railway networks in Britain, and 14 train operating companies took strike action on October 1.

The walkouts come after a row over job security, pay and working conditions, and another action is scheduled for Saturday.

The latest strike will effectively shut down the railway network, said the National Union of Rail, Maritime and Transport Workers.