"Most people would find it pretty extraordinary that [IPSA] would be recommending a large rise for MPs at a time when living standards in this country are under pressure," Chief Secretary to the Treasury Danny Alexander told ITV News.
"I would still appeal to IPSA even at this late stage to recognise that the economic climate - the climate of pay for people in the public sector particularly - is one of continuing restraint and that same principle should be applied to MPs," he said.
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His mother Princess Diana was killed in a car crash in Paris in 1997 when he was just 12 and his brother William was 15.
The 21-year-old, who was arrested on Sunday, also allegedly injured two other people in the attack in the German city of Reutlingen.
She was going to the aid of a family member who got out of the car in the middle of the park and was dragged away by a different tiger.