Balls briefing may be last before he quits to stand for Parliament

Ed Balls, the Chancellor's chief economic adviser, made what might be his last Budget briefing to journalists yesterday.

Ed Balls, the Chancellor's chief economic adviser, made what might be his last Budget briefing to journalists yesterday.

The Chancellor's aide whizzed through the Red Book setting out "the fiscal arithmetic" in an attempt to explain the finer detail of the spending plans.

For eight budgets, Mr Balls has worked with the Chancellor, but the Oxford and Harvard-educated economist is expected to resign to seek the nomination for the safe Labour seat of Normanton. The constituency is being vacated by Bill O'Brien and neighbours Pontefract and Castleford where his wife, Yvette Cooper, is the MP.

Mr Balls, 37, who writes a column for the local paper and spends weekends in the area, is the favourite to take the seat. If he is chosen, he is expected to be catapulted on to the front bench, and has even been tipped as a future Chancellor.

Yesterday Mr Balls, a former Financial Times leader writer, raided his economist's vocabulary to explain the Budget. The phrases "setting out the envelope" and "margin of caution" tripped off his tongue, although he also managed a pop at the Tories, whom he accused of aiming to cut public services.

Mr Balls is expected to be missed by Mr Brown, who regards him not only as a prudent adviser but as a close political ally and friend.