Elections mailings and Christmas cards could be affected by industrial action aimed at saving workers’ jobs.

The main union at Royal Mail on Monday rejected an offer the company says is aimed at avoiding a strike that could affect mail deliveries before a general election in December.

Royal Mail told the Communications Workers Union (CWU) that if it removed the threat of strike action for the rest of 2019, the company would enter talks without preconditions.

CWU General Secretary Dave Ward called Royal Mail’s offer a “stunt” for which the union would not fall.

“If Royal Mail are serious about avoiding disruption to the postal service they will put an offer on the table that protects our members’ jobs, terms and conditions and the service they provide to the public and businesses,” Ward said in an email.

The CWU last month voted by 97 percent in favour of a nationwide strike, saying the company had failed to adhere to a pension deal agreed last year.

Royal Mail said it had honoured the 2018 agreement with the union, with two pay increases, a working hours reduction and joint lobbying of the government for a new pension scheme.

On Twitter, CWU said its strike ballot was called well before the election, and that if a previous government led by the Conservative Party “hadn’t forced the outrageous privatisation of Royal Mail we wouldn’t be here”.

An early general election is set for December 12 after Conservative Prime Minister Boris Johnson could not get his deal for the United Kingdom to leave the European Union through Parliament by a deadline of October 31.

“In the event of industrial action in the run-up to a general election, election mail will be our number one priority. We will invest significant resource to seek to ensure a seamless process for the handling of postal election material,” Shane O’Riordain, Royal Mail managing director of regulation and corporate affairs, said.

Royal Mail volunteers would work on processing and delivering election mail, he added.

“A binding commitment from the CWU to remove the threat of strike action during the period of any general election is vital to ensuring a seamless electoral process in relation to postal votes,” O’Riordain said.

Royal Mail said it was meeting the CWU to discuss the union’s request for increased payments postal workers for delivering poll cards and mail sent by parliamentary candidates.

The CWU said it had not set a date for any strike.

Royal Mail faces the threat of renationalisation from the opposition Labour Party, which also plans to return utilities and train companies to public ownership.

Labour moved sharply to the left under Jeremy Corbyn, who hopes to exploit turmoil over Brexit to win power.