Milford Haven Port Authority (MHPA) has gone to the High Court in a bid to stop its pilots and launch crew from taking strike action this Thursday.

A MHPA spokesman confirmed the authority 'questioned the legality of the actions' and had presented an injunction to the High Court in London on Monday afternoon. A ruling is expected this afternoon.

Both sides say they have presented offers during last ditch talks but no deal could be agreed.

Unite Trade Union Regional Officer Allan Card said: "We offered up to a 28-day postponement of strike action to allow negotiations to continue, that was turned down by the authority.

"Whether the injunction is granted or not, which I'm not convinced it will, it is just a technicality.

"We will just go through the same process again."

A MHPA spokesman said the authority was prepared to go to the binding arbitration, but as yet had received no response to that offer from Unite.

Despite continued meetings with both sides and ACAS, the independent conciliation service, Mr Card said 'insufficient progress' had been made.

Last week formal notification of strike action was served by the trade union. A complete withdrawal of labour is scheduled to take place on Thursday and Friday, with 'work to rule' action planned for Saturday. Emergency cover would still be provided.

MHPA Chief Executive Ted Sangster said discussions were continuing and the authority was committed to resolving the dispute through dialogue.

Mr Sangster said: "The authority is disappointed that industrial action is planned which could potentially damage the port's reputation, impact on customers and the wider needs of the country, but is hopeful that a resolution can be agreed at the meeting and has indicated that it is prepared to go to binding arbitration, if necessary."

The dispute concerns changes that are being introduced by the authority to its pension scheme and provision of pension benefits.

"Like many organisations across the UK, the authority's defined benefit pension scheme faces a large and growing deficit that is unsustainable.

"The authority believes that the revised defined benefit scheme remains a good package, from an employer that has carefully considered the needs of both its employees and the business," said Mr Sangster.

Preseli Pembrokeshire MP Stephen Crabb is encouraging both sides to talk.

"I am surprised and disappointed that Unite is pushing this industrial action so far," he said.

"The strike comes at an incredibly sensitive time for many of the projects based on the Haven, especially the oil refineries, and sends out the worst possible signal to the companies that are investing in Pembrokeshire and creating new employment for local people.

"There are a great many of Unite's own members, whose own jobs are linked to the local oil and gas industry."

The authority said it is working closely with its customers to ensure that contingency plans are in place to minimise disruption if strike action does go ahead.

Port customers Chevron and South Hook LNG both have vessels scheduled to arrive into the haven during the strike.

A Chevron spokesman said: "Chevron is aware of a possible strike and anticipates minimal, if any, impact to its UK customers.

"However, if this industrial action continues we believe there could be an economic impact on Chevron's Pembroke refinery operations.

"We would therefore encourage both parties to reach prompt resolution."

A South Hook spokesman said: "We are continuing to work closely with the MHPA and the appropriate stakeholders in our day to day haven related business operations. "Our focus is the safety and integrity of our terminal."