The man, now in his 40s, signed a contract with his mother in 1997 in which he agreed to pay her 60 per cent of his monthly income after qualifying.

He argued before Taiwan’s top court that the contract was invalid because it was wrong to demand financial return for raising a child, but the court ruled that the deal — struck when he was 20-year-old — was binding.

The mother, named only as Ms Luo, said she spent hundreds of thousands of pounds as a single mother to have her two sons trained as dentists.

However, she was concerned that they would not care for her in old age and signed a deal that they would pay back the school fees up to £1.25 million.

The brother settled the contract for a smaller amount, but the man who refused to pay has been ordered to make back payments including interest.