LLOYDS Bank has backed its chief executive after he faced calls to resign over an expenses bill he ran up during an alleged fling with a former adviser to Tony Blair.

Antonio Horta-Osorio was spotted enjoying days out with Dr Wendy Piatt on a business trip to Singapore, where he represented the State-backed bank.

The pair met up at his £350-a-night room at the five star Mandarin Oriental hotel, which he booked using his Lloyds Bank address.

His bill showed he spent £3,276 on his room and on mini-bar and room service charges during his six-night stay, plus an extra £550 on two visits to the hotel spa.

Questions were raised over whether Mr Horta-Osorio’s expenses were paid by the bank, which received a £23.7 billion bailout from the UK Government during the financial crisis and is still 9.2 per cent owned by the taxpayer.

However, a spokesman for Lloyds Banking Group insisted Mr Horta-Osorio, who has been married for 25 years and has three children, had paid his own personal expenses during the Singapore trip. He added: “In this case there is no breach of our policy and the personal expenses are paid for by Antonio.”

Lloyds has refused to answer questions about his relationship with Dr Piatt, director general of the Russell Group of universities. She is not married.

Dr Piatt, who previously worked for the Institute for Public Policy Research, is understood to have travelled to Singapore to meet university chiefs and there is no suggestion she has wrongly claimed costs or expenses. Her room was paid for by the Russell Group.