BRITAIN’S shoddiest rail privateer has hurtled further into chaos, press-ganging managers into filling guards’ posts on the chronically understaffed Southern franchise.

Transport union RMT revealed that every manager with the necessary safety certificate had been sent back to the carriages even though the Govia Thameslink Railway (GTR) has ditched 341 trains a day, blaming high levels of staff sickness for its woes and claiming the emergency timetable would fit with available staff numbers.

“It was yet another pack of lies from a basket-case franchise in terminal meltdown,” blasted RMT general secretary Mick Cash.

“They are now being forced to press-gang managers to plug the gaps in what they themselves describe as an emergency situation.”

GTR — the worst-performing franchise in Britain, according to the latest Network Rail figures — has provoked fury among hard-pressed staff and fed-up commuters alike, with passengers kicking off a campaign of action against the dilatory privateer with a protest at London’s Victoria station on Monday.

Mr Cash pinned the blame on a “toxic combination of gross managerial incompetence and the failure to recruit and train enough guards and drivers to fill the rosters.”

And London Mayor Sadiq Khan joined the chorus of voices calling for GTR to lose the lucrative franchise yesterday, saying he was appalled at the “unceasing misery” being inflicted on passengers.

He called on the Department for Transport to take over Southern rail services.

“Passengers’ frustration at such a disgraceful level of service is obvious and it is justified,” Mr Khan said.

“This utter mess is now an embarrassment to our city, it is an insult to hard-working Londoners who pay their fares and it must be fixed.

“That is why I am calling on the government to strip Southern of its franchise and take over the temporary responsibility of running these services.”

But Transport Secretary Patrick McLoughlin continued his steadfast backing of Southern’s intransigent management, claiming RMT’s opposition to axing safety-critical staff was “absurd.”

His department has backed GTR to the hilt in the dispute as part of of a wider campaign to get rid of train guards.

The union branded the Tory minister’s attack on front-line staff “disgraceful.”

“The company has repeatedly lied about ‘staff sickness’ when it is, in fact, fleet breakdowns and shortages, systemic mismanagement and a failure to recruit adequate staff numbers that has tipped Britain’s biggest rail franchise into daily chaos,” fumed Mr Cash.