Image copyright CWU Image caption The strike will be the third in this series of protests

Managers at Crown Post Offices will hold a third strike on Saturday 3 December in a continuing dispute over jobs, pensions and branch closures.

Unite said the 24-hour walkout would disrupt overseas Christmas mail and parcels on the peak day for such mail.

It will involve more than 700 managers.

They will be joining a strike by the Communication Workers Union, which is in dispute over jobs, the franchising of Crown Post Offices and the closure of a final salary pension scheme.

Crown Post Offices are the larger branches that are usually located in High Streets.

In April 2016, the Post Office announced plans to transfer up to 61 branches into WH Smith stores over the following year.

It said the move was part of a 10-year plan to cut costs and save cash, and would act as a way of "safeguarding the future of the network."

'Extremely sorry'

But the CWU said it faced up to 2,000 job losses as a result and it would lead to the closure of its pension scheme.

Unite's officer for the Post Office, Brian Scott, said: "We are taking this action because the management refuses to talk in a constructive manner about the pension scheme which is currently in surplus to more than £143m.

"This is the retirement income of our members which is at stake and we are not going to stand idly by and let them lose thousands of pounds when they retire."

Post Office spokesman, Mark Davies, said: "We are extremely sorry that the unions are attempting to disrupt services for people sending parcels and cards to loved ones in the run-up to Christmas.

"However, we would like to reassure our customers that, if a strike goes ahead on December 3, it will impact less than 300 of our 11,600 branches. It will be business as usual in 97% of our network."

The first 24-hour walk-out took place on 15 September and the second on 31 October.