Lord Falconer of Thoroton, the Cabinet Office minister, disclosed that the figure had increased from 130 to 199 although he denied suggestions that there were any plans to move into bigger offices.
Mr Blair said, in a parliamentary written reply last month, that just over pounds 1m had been spent on revamping 10 Downing Street, partly to transform state rooms on the top floor into office space. Lord Peyton of Yeovil, the former Tory minister, asked why "so much money" was being spent on the refurbishment, adding: "The rather bigger staff which the Prime Minister is said to require today is now bursting out of the seams of Number 10 and looking for better, bigger and newer accommodation.
"Is the pressure due to the very large image-making staff, which is the busiest and most successful department in the Government?"
Lord Falconer insisted: "They are not bursting out at the seams. There are no plans either to move or to increase the size of the accommodation.
"The number of staff has been increased. But the Labour Party made clear before they got into office that they would have a strong centre and that's what they have got."