Conductors on Southern Rail have voted to go on strike over a "comprehensive breakdown" in industrial relations.

The Rail, Maritime and Transport union said a ballot returned a 70% majority in favour of walkouts, with a bigger figure for other forms of industrial action.

The union's executive will consider the next move and will have to give seven days notice of any strikes.

The dispute is over issues including staffing and rosters, which the union claims are causing disruption to services.

RMT general secretary Mick Cash said: "The staffing shortages on Southern are a disgrace and are creating daily problems. Our members have now shown just how angry they are in this magnificent ballot result which will now be considered by the union's executive.

"This is a vital and lucrative franchise where commuters pay thousands of pounds a year to travel on services that are chronically understaffed and RMT members have had enough of it.

"This union will not sit back while staffing levels are pared to the bone on rail franchises and our members run ragged solely in the interests of private company profits.

"RMT remains available for further talks and we hope that in light of this ballot result the company will now see sense."

Southern runs some of the busiest services in the country, including commuter routes to London Victoria.