Craig Oliver
Craig Oliver is one of the top earners, with a salary of £140,000Reuters

The UK government has "failed" to get the cost of politics down as the wage bill for special advisers surged to £8.4m in the last year.

The figures from the Cabinet Office revealed that the number of political aides to ministers jumped from 93 to 103, increasing the salary total by £1.2m ($1.8m, €1.5m).

The Coalition Agreement promised that the government would "put a limit on the number on special advisers", however, the number of political aides and their cost have continued to rise.

David Cameron has 26 special advisers, the most in the government, while Nick Clegg has 20.

Craig Oliver, the director of communications for Downing Street and a former controller of English, BBC Global News, is one of the top earners, with a salary of £140,000.

The Coalition Agreement promised that the government would "put a limit on the number on special advisers", but the number of special advisers and their cost continue to rise.

"Another day, another broken promise from Cameron and Clegg," said Angela Eagle, the shadow leader of the House.

"Cameron promised to get the cost of politics down but under him the number of Special Advisers spirals ever upwards – the public are now picking up bill of over £8m to pay for his appointees."

The data showed that there were only 38 special advisers in 1996/7 – the numbers have increased to 74 in 2008/9 and now is at a high of 103 in 2013/14.

A Cabinet Office official said: "Workforce reductions and pension reforms saved £4.7bn last year, compared to a 2009/10 baseline.

"Special advisers perform an important function and their average salary cost is 8% lower now than under the previous government."