It was intended as a landmark to rival the Statue of Liberty. But when a 30ft bronze sculpture of a couple embracing was unveiled at London’s St Pancras International station last year, critics put in the boot.

Despite its popularity with tourists, The Meeting Place, the official name of the £500,000 statue, was described by experts as “truly horrific”, “kitsch” and “dreary and mournful”.

Now Paul Day, its sculptor, is at the centre of an even fiercer controversy after announcing plans to decorate the statue’s bare plinth with a bronze frieze featuring an image of a commuter falling into the path of a train driven by a Grim Reaper figure.

Captured in the reflection of a giant pair of sunglasses, the victim is surrounded by onlookers, including a woman with an outstretched arm – either pushing the man over the platform edge or attempting to pull him back from certain death. “It’s ambiguous, it’s not clear,” said Day.

The new work of art, commissioned by London & Continental Railways (LCR), the owner of St Pancras, will be seen from next year by the millions of travellers who pass through Britain’s main Eurostar terminal.

This weekend it was condemned as “insensitive” and “sensationalist” by the families of rail suicide victims and Aslef, the train drivers’ union.

Day, however, claimed the frieze was a deliberate contrast to the “ideal” of the towering lovers embracing above. “It is about daily life – about the hopes and fears, the loves, the joys, the loss and tragedy that are bubbling along together in human life,” he said.

The bronze relief will feature a variety of scenes depicting life on the railways, including images of soldiers going to war and emergency workers dealing with the 7/7 bombings.

“If certain images cause a small amount of offence, I’m sure that will be heavily compensated for by a sense of joy . . . that the other images will give,” said Day. “It’s balance, it’s contrast. The overall effect, I think, will be very positive.”

Day, 41, whose work also includes the Battle of Britain memorial on London’s Embankment, said he was “absolutely not” seeking to portray train drivers as killers.

However, he admitted that some members of an LCR selection panel – which included Stephen Jordan, the company’s managing director – who approved the frieze had found the 2ft 6in death scene “uncomfortable”.

The panel had rejected a separate section of the bronze relief that showed a leering thug giving a one-finger gesture and a young woman straddling the lap of her lover.

Last night Kate Redway of the Samaritans said: “It’s really important that any images don’t portray suicide methods. Research has shown that it can lead to an increase in copycat deaths, particularly among young, vulnerable people.”

Rail union bosses called for the frieze to be scrapped. “Every train driver in this country will be sickened by this image,” said Keith Norman, general secretary of Aslef. “A body lying under their wheels is the dark cloud that troubles drivers’ every working day. To see these respectable, professional men and women portrayed as agents of death is insulting, facile and malicious.”

It is not the first time that the depiction of suicide on the railways has triggered a backlash. Earlier this year train drivers picketed the premiere of Three and Out, a film starring Mackenzie Crook and Imelda Staunton.

It was a comedy based on the fictional premise that if a Tube driver hits three passengers in a month he is pensioned off with 10 years’ full pay.

LCR said: “The frieze depicts heroic images as well as tragic. It will be a talking point and that is testament to the character of St Pancras International and to this bold commission.”

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