Tata Steel has come one step closer to facing a strike in the UK, with the unions giving the steel company official notice about their intention to begin balloting thousands of members for industrial action next month.

Unions are urging their members to vote for “strike action and action that is short of strike action,” following the failure of talks on “unnecessary and unjustified” plans to close the company’s defined benefit pension scheme.

Ballot papers will be posted to union members on May 6, and the ballot is expected to end on May 29. Three unions — Community, GMB, and UCATT — gave notice of the plans on Monday, while the fourth, Unite, is expected to give notice in the next few days.

In a statement, Roy Richhuss, Chair of the National Trade Union Steel Coordinating Committee, said that the unions had had no choice but to go ahead with the ballot. “Unfortunately there is no sign of Tata showing any willingness to work in a collaborative and co-operative spirit and re-enter meaningful discussions with trade unions about the future of the British Steel Pension Scheme.”

He said that Tata had rejected the unions’ “constructive offer” to discuss changes to the scheme.

Unions estimate that the scheme had around 143,000 members at the end of last year, including just over 17,000 employees, with assets of around £13.6 billion at the end of November.

“We have made it clear to the unions that our door remains open,” said a Tata Steel spokesperson, adding that the company remained committed to providing employees with competitive future pension provision.

According to Tata Steel, it had tabled proposals to the national officers of unions whereby the final salary scheme would remain open to future accruals subject to a number of modifications. “As agreement with the trade unions on these proposals could not be reached, the company has initiated a 60-day statutory consultation period with scheme members on the proposal to close the scheme,” said the spokesperson.

“The consultation process provides opportunities for employees to comment on the proposals and to suggest alternatives that they wish the company to consider, other than the proposal of closure to future accrual.”

Over the past few years, British firms have been closing final salary pension schemes, which are based on income at the time of retirement, and place the responsibility of paying pension income directly on the employer, moving employees onto defined contribution schemes (these move the investment risk onto employees), in a bid to cut costs.