Announcing Granada's last interim results before the two companies merge in February, Allen said £43 million had already been saved since the merger was approved, and that a further £57 million of savings had been identified.
He claimed there was a one-off cost of £73 million to achieve the additional savings, raising fears that there could be more redundancies than expected.
The creation of a single ITV sales house is expected to lead to hundreds of job losses.
Elsewhere, Allen announced that ad revenue was down 1 per cent in the year to September and that the improvement in ITV's audience performance meant that it was the cheapest to advertise on ITV in five years. Granada's profit before tax was up 14 per cent to £179 million.
Carlton also announced its interim results today. Profit before tax was up 47 per cent to £79 million while turnover dropped 1 per cent.
Allen said: "We are making rapid progress towards completing our merger with Carlton. Our investment strategy in ITV's schedule is working, cost savings are ahead of plan and we are generating strong cash flows. We are now focusing on driving ITV forward, growing the TV advertising market and building the leading package of commercial free-to-air channels in the digital world."