Members of train driver’s union ASLEF have narrowly rejected an offer to end the dispute over driver-only trains operated on Southern railway lines.

The union announced Southern staff voted by 372 votes (51.8 per cent) to 346 (48.6 per cent) against the deal on Monday, April 3.

Under the proposed deal staff would accept driver-only operated trains on Southern services.

ASLEF general secretary, Mick Whelan, said: “We understand and support the decision arrived at in a democratic vote by our drivers and will now seek new talks with the company and work to deliver a resolution to this dispute in line with the expectations of our members.”

Following the referendum result Andy Bindon of Govia Thameslink Railway, Southern’s parent company, said: "It's a hugely disappointing outcome for our passengers, particularly as the agreement carried the full support and recommendation of the ASLEF leadership.   

“We have shown a willingness and desire to find a solution to their dispute and we will now, once again, sit down with the union, understand the issues which led to this regrettable decision by the drivers and try and find a way forward to resolving it."

It is the second proposal that members have voted on after they rejected a proposal to operate trains without a guard in certain circumstances.

The union argued the move reduced passengers’ safety as guards would hand over their responsibility for opening and closing carriage doors to drivers.

But Southern have rebutted the union’s claim and said driver-only trains were safe.

Passengers have endured months of disruption after the Rail, Maritime and Transport Union (RMT) began industrial action in April 2016 before ASLEF joined in December.

Read more: RMT members including Southern train staff to stage 24-hour strike on Grand National day

RMT union members at Southern, Merseyrail and Arriva Trains North will stage their next strike this Saturday, which has been deliberately staged to cause travel misery for tens of thousands of passengers on their way to the Grand National at Aintree in Liverpool this weekend.