Workers on Virgin Trains East Coast are to stage a 48-hour strike in a row over the role of guards and jobs.

Members of the Rail, Maritime and Transport (RMT) union will walk out of the east coast service, which travels between London and Scotland, on April 28 and 29.

The move follows strikes at three other train operators last Saturday in bitter rows over staffing.

The RMT has been seeking an "explicit clarification" from Virgin on the role of the guard.

It wants specific reassurances a new position of train manager will retain the safety-critical roles and training currently held by train guards.

The company has responded by confirming the "safety-critical duties" of the guard will remain on the train.

In a statement, the RMT said the "vague and non-committal mantra" was a "mealy-mouthed form of words which give no reassurance to RMT members in the front line".

The RMT also said consultation over "widespread on-board changes" has been going on for more than a year, adding the company had implemented the changes from March with no agreement with the union.

RMT general secretary Mick Cash added: "It is simply appalling that Virgin East Coast have refused to give the most basic assurances on the safety-critical role of the guard on their trains continuing into the future.

"Their contemptuous attitude has unleashed a tidal wave of anger at the grassroots and the action we have agreed to put on is simply a reflection of the disgust and frustration at months of ducking and diving by the company."

Virgin Trains said it will run a near-normal timetable during the industrial action.

The company said it has made changes to customer-facing roles on board train which will see a single person take responsibility for the "customer experience".

"This will mean a better experience for customers. It also has zero impact on safety. We have repeatedly assured the RMT that the safety-critical role of the guard will remain on board, with the new train manager role taking responsibility," said a statement.

David Horne, managing director for Virgin Trains on the East Coast, said: "We have worked hard to ensure there are comprehensive contingency plans in place and I want to reassure our customers that our timetable will be almost completely unaffected during this walk-out, as well as during any subsequent strikes by the RMT.

"Passengers can book and plan their journeys as normal and with confidence. The changes we have made are part of the customer-centric revolution that's under way on the East Coast.

"We've already completely refreshed our entire fleet of trains with all new interiors, and next year we will have our ground-breaking Azuma trains coming into service. Alongside more modern trains, we want a modern customer service proposition - one that focuses firmly on the customer."

He added: "The on-board changes came into force in March. Last week - the first full week since the changes - saw us achieve our second highest customer satisfaction score since taking over the franchise, so we are confident the changes are benefiting customers.

"With our guarantees that there will be no compulsory redundancies, no impact on safety and a near-normal timetable in place during the walk-outs, this pointless strike will cost RMT members pay for no reason, and we urge the union to rejoin us for further discussions."