IBM signalled its growing confidence in an early rebound for the technology sector as it revved up its share buy-back plans on Tuesday with the commitment of an extra $5bn.

Though it did not say how quickly it would spend the money, the extra allocation to the buy-back plan, on top of $4.2bn left over from an earlier board authorisation, appeared to point to a re-acceleration of share repurchases as customers grow more confident about spending money on tech again.