In a bid to resolve the pension dispute with its trade unions, Tata Steel today said it has approached British conciliation service Acas.

"We have contacted Acas to bring in independent expertise in mediating a resolution to the UK pension dispute. We have requested Acas to immediately approach the National Trade Union Steel Coordinating Committee to ask them to attend talks," Tata Steel's European operations Executive Director of Human Resources Tor Farquhar said in a statement.

Acas (Advisory, Conciliation and Arbitration Service) provides free and impartial information and advice to employers and employees on all aspects of workplace relations and employment law.

Trade unions representing workers of Tata Steel in the UK had announced "strike action" on June 22 over proposed changes in the company's pension scheme -- the biggest industrial action in the UK in nearly three decades.

"We have been talking to the trade unions since November 2014 to develop a fair and sustainable pension scheme for all UK employees. The company and unions agree that changes need to be made to tackle the scheme's projected shortfall of up to 2 billion British pound," Farquhar added.

The company said, industrial action, consisting of an overtime ban and a work to rule, is currently scheduled to begin on June 16, with a one-day strike planned for June 22.

"It remains the company's intention to provide a high quality and competitive pension scheme for our employees while continuing Tata Steel's significant record of investing in its UK assets so we can build a sustainable business here," he said.

Tata Steel employs over 17,000 workers across four sites in Wales in Port Talbot, Newport, Flintshire and Carmarthenshire, as well as sites around England including Corby, Hartlepool, Rotherham, Scunthorpe, Teesside and York.