Bosses at the trade union whose strike action has caused years of rail commuter misery are enjoying a pay bonanza, with inflation-busting increases to six-figure salaries.

The Sunday Telegraph can reveal that RMT general secretary Mick Cash climbed the rankings as one of the best paid union boss, taking home £162,004 last year - this despite the comparatively small size of the organisation that has held thousands of rail users to ransom.

Senior assistant general secretary Steve Hedley’s remuneration rose by a fifth to £105,499. Assistant general secretary Mick Lynch took an £18,000 pay cut but still received £90,307. President Michelle Rodgers’ “allowances and expenses” totalled £57,401.

The as-yet unpublished draft figures for 2018, seen by the Telegraph, were branded “absolutely obscene” and “hypocritical” by MPs and economic think-tanks.

Mr Cash, who took over as RMT leader following the sudden death of Bob Crow in 2014, has led a long-running fight with rail bosses over the operating of carriage doors.

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Bitter rows with train companies the length and breadth of the country have resulted in waves of industrial action. The most recent of these has seen the South Western network, which services Britain’s busiest station Waterloo, crippled by week-long walkouts.

Last year Northern rail was brought to a near-standstill on the run up to Christmas - again over guards' operation of doors - forcing shoppers to stay at home and hitting high street businesses on both sides of the Pennines during what is usually the busiest time of the year.

The industrial action has pushed train company finances into the red. South Western, which is run by listed transport company FirstGroup, has written down its investment in the franchise by more than £100m

Passengers using Southern, Govia Thameslink, Merseyrail train lines and the London Underground have also suffered in recent years by rolling industrial action by the RMT.

Conservative MP Jack Brereton, a member of parliament’s Transport Committee, said: “It’s absolutely obscene.

“To hold fare payers to ransom is totally unacceptable,” he said, adding that union bosses pay “Is setting a dangerous precedent”.

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The RMT salaries will likely raise eyebrows at the TUC’s 2019 Congress, which starts in Brighton today. Mr Cash’s pay far exceeds that of the general secretary of Britain’s biggest trade union Unison. Boss Dave Prentis is paid £138,551 to lead Unison’s 1.4 million members. The RMT represents just 85,000 workers.

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