The National Federation of SubPostmasters (NFSP) has called on the government to halt the sale of Royal Mail until the promise of new work has been delivered on.

The government announced that the IPO (Initial Public Offering) would take place in the coming weeks. It is estimated that the Royal Mail stock flotation could be worth £3bn.

The NFSP said a failure to protect post offices would amount to a reckless gamble with the future of the post office network and urged the government to retain a stake in Royal Mail.

Currently a third of all subpostmaster incomes are generated from work carried out for Royal Mail.

NFSP general secretary George Thomson said: “I am extremely disappointed and concerned that the government is pressing ahead with a plan that will undoubtedly jeopardise the future of thousands of post offices.

“We simply have not had the promised new government work that needs to be delivered before the sale of Royal Mail and which would safeguard the future survival of an independent Post Office.

“We are now calling on the government to halt the sale until we can be sure that new work is forthcoming. We are also urging ministers to retain a share in Royal Mail to ensure government has the ability to protect the interests of post offices and their customers, which are already under serious threat.”

Communications Workers Union general secretary Billy Hayes added that the sale would lead to a diminished service. “We remain convinced that privatisation is the wrong decision for Royal Mail. It would be bad for customers, bad for staff and bad for the industry. Privatisation would put jobs and services at risk and lead to higher prices for customers.”