North Sea oil workers are to stage a series of strikes in a dispute over pay and working time.

Members of Unite working on the Alwyn, Dunbar and Elgin oil and gas platforms operated by Total E&P will walk out for 24 and 12 hours on five days between July 23 and August 20.

There will also be a continuous ban on overtime starting on July 23, following a vote in favour of industrial action.

Unite regional officer Wullie Wallace said: "The overwhelming vote in favour of strike action demonstrates the fury at Total's proposals to impose changes to the working practices and conditions on its three platforms.

"There remains a closing window of opportunity for Total to behave responsibly and engage with Unite to revise its current offer.

"If Total does not wish to negotiate, they will be left in no uncertain terms of the strength of feeling of Unite members which will lead to widespread disruption of the company's operations."

Twelve-hour strikes will be held on July 30 and August 13, with 24-hour walkouts on July 23 and August 6 and 20.

Unite members employed at Total's Shetland gas plant have also voted for industrial action in a dispute over changes to their rota system.

Jean-Luc Guiziou, managing director of Total E&P UK, said: "Our workforce at the Shetland Gas Plant and on the Elgin, Alwyn and Dunbar platforms do a very good job and we will do our best to work towards a resolution of this dispute.

"I know from talking to our workforce that we can find a negotiated solution. We have started a structured process of meetings and workshops that will hopefully allow us to reach a consensus.

"By moving to a 3/3 rota, we'll be in a much stronger place to grow our business and increase operational excellence. Our objective is to seek a rota system that both enhances overall safety and is the most efficient - in this way we will ensure the long term sustainability of our business in the North Sea."

Mr Guiziou said he looked forward to a "constructive dialogue" with offshore staff and their representatives.