Image caption Cher Lloyd is one of the X Factor contestants which is broadcast on ITV at weekends

ITV programmes are aimed towards the "lowest common denominator", channel bosses have said.

ITV chairman Archie Norman said the broadcaster, home to shows such as Coronation Street and The X Factor, is stuck in a "ratings rat race".

ITV chief executive Adam Crozier also told the Lords communications committee that ITV's schedule had a "remarkable lack of diversity".

He added that he would like to start investing in arts and factual shows.

The former Royal Mail chief executive, who took up the top job at ITV in April, criticised the Contract Rights Renewal.

He wants the Contract Rights Renewal (CRR), which is the framework that governs air time sales deals, to be axed.

CRR was introduced following the merger of Carlton TV and Granada into ITV in 2003 and linked the amount that advertisers spend on the channel to ITV's audience share - which means advertisers pay less for lower audiences.

"Ad revenue has fallen by about 22% since CRR was introduced. That has led us to invest less and less in programmes," Mr Crozier said.

He added that if the CRR was ditched, then ITV would not have to "chase volumes of impact that would allow us to have a much more diverse schedule".

He said the ITV schedule was limited because "we have to invest in programmes that drive the biggest audiences, rather than the most unique audiences".

ITV axed its flagship arts programme The South Bank Show earlier this year while Simon Cowell has just signed a new three-year deal with the channel to broadcast The X Factor and Britain's Got Talent.

In January, the Competition Commission rejected an ITV proposal that the broadcaster should have more flexibility in how much it charges advertisers.

But Mr Crozier has called on culture secretary Jeremy Hunt to look at CRR and its benefits.

ITV has claimed it has lost about £262m in revenue since the CRR was introduced in 2003.