ITV's news special on Prince William and Kate Middleton's engagement drew an average of 5.8m viewers peaking at 6.3 million last night.
According to figures revealed by the channel to Press Gazette, ITV1 had a 26 per cent audience share in the 7pm to 7.30pm slot, which would normally have been taken by soap opera Emmerdale.
The BBC's One Show also ran pooled footage of the exclusive interview with the pair by ITV political editor Tom Bradby and it attracted some 6.48m viewers in the same slot.
This compares with the ITV early evening news at 6.30pm usually attracts between 3.5m and 4m viewers on ITV1.
The interview with William and Kate was conducted by Bradby yesterday afternoon at Clarence House, with Press Association also on hand to produce a transcript. The edited version of the broadcast interview was made available to other broadcasters with a 7pm embargo.
The prince's press secretary Miguel Head told journalists yesterday that 'the couple asked to record this interview specifically with Mr Bradby, whom they have both known for some time.'Bradby was formerly royal correspondent for ITV News.
Head also urged journalists to respect the privacy of the Middleton family saying: 'We have a very good working relationship with all of you, but, if I may, I would also like to take this opportunity to remind everyone that the Middleton family remain private individuals.
'Particularly, may we ask you to remind your picture desks about PCC rules concerning the use of photographs that may have been taken following harassment or a breach of privacy. If you have any concerns about a photo, please refer your concerns to the PCC or to the Clarence House press office."
He said that Mr and Mrs Middleton have let it be known that 'they will not be granting any exclusive interviews or special favours to any media organisation".
The royal wedding scoop crowns an impressive week for ITV News.
On Monday night UK news editor Keir Simmons exclusively revealed on News at Ten that the Government has agreed to pay millions of pounds in compensation to at least seven former Guantanamo detainees who say they were tortured.
Also on Monday, ITV News broadcast an interview with freed Burma democracy campaigner Aung San Suu Kyi carried out by John Irving (the BBC also obtained an interview with her).
On Sunday ITV News obtained some exclusive footage of the moment Britons Paul and Rachel Chandler were handed over by their kidnappers in Somalia.