Royal Mail could be on the verge of its very first strike since the company became privatised in 2013.

Workers voted massively in favour of industrial action in a bitter dispute over pensions, pay and jobs.

In total, 89 per cent of members of the Communication Workers Union (CWU) backed walkouts on a turnout of 73 per cent of the 110,000 balloted.

The CWU believes it is a "watershed" moment for unions as well as the Royal Mail.

The union's deputy general secretary Terry Pullinger said: "This ballot result is hugely significant and demonstrates a strength of feeling that can only be translated as a massive vote of no confidence in the managerial leadership of the Royal Mail Group and the direction that they advocate.

"Any sense of vocational spirit and working together with management has been lost in a climate of fear and insecurity.

"This massive failure in trust has created a breakdown in relationships and a toxic environment where working together to solve difficult problems has become almost impossible.

"The managerial leadership has failed and should resign or be sacked."

The union accused the company of "unilaterally" closing its defined benefit, or final salary, pension scheme, with new entrants going into an "inferior" scheme which will leave them in "pensioner poverty."

The union is also in dispute over pay and issues such as delivery office closures.

Mr Pullinger declined to say whether the strike could interfere with the Christmas post,

A statement by Royal Mail said: "A ballot result for industrial action does not necessarily mean there will be industrial action.

"Royal Mail is committed to further talks as a matter of urgency, to reach agreement with the CWU.

"There are no grounds for industrial action. We want to reach agreement."