Britain’s Got Talent finalists Richard and Adam Johnson have become the first act this year to top the album charts for four consecutive weeks.

The Welsh siblings – who finished third in the BGT final in June, held on to the top spot by the narrowest of margins with The Impossible Dream, outselling nearest rivals Rudimental by just 2000 copies.

And in doing so they set a new chart record for the year, beating Justin Timberlake’s The 20/20 Experience for the longest consecutive stay at number one since the year began.

That album topped the charts for three straight weeks in March and early April.

The duo are also tied with the soundtrack of the movie Les Miserables for the most weeks at number one in 2013.

However that album’s run at the top was non-consecutive, spending a fortnight at the top before being dethroned for one week and then returning for a further two weeks.

Richard and Adam’s performance on the Britain’s Got Talent final achieved notoriety after a mystery woman – later revealed as viola player Natalie Holt – walked on stage during their performance and pelted Simon Cowell with eggs.

They are the second BGT act from this year’s series to achieve chart success, after teenager Gabz Gardiner scored a top five hit with her track Lighters last month.