Should Manchester and Liverpool combine for economic gain?
26 February 2014 Last updated at 10:42 GMT
Manchester and Liverpool should combine infrastructure and population for economic gain, former Goldman Sachs economist Jim O'Neill has claimed.
Speaking to BBC Radio 4's Today programme, he explained that "large masses of people living close together typically generate the most economic activity", yet the UK's only city of significant population was London.
But BBC Radio 2 presenter Janice Long said that "the differences and the characters" of the two cities needed to be maintained.
First broadcast on BBC Radio 4's Today programme on Wednesday 26 February.