Britain's Got Talent draws complaints over lap dance and child singing about one-night stand

David Walliams persuades Simon Cowell to join Keri, a 43-year-old contestant on Britain's Got Talent, on stage. (PA)

Some viewers have grumbled that ratings-winning Britain's Got Talent was not suitable for family viewing after featuring a lap dance and a child singing about a one-night stand.

ITV show BGT trounced The Voice as the two shows clashed for the first time this year, drawing in excess of five million more viewers than its BBC rival.

But some who tuned in on Saturday posted online messages about how the show was not exactly wholesome viewing and led to embarrassment for some who were watching with youngsters.

The first edition featured dancer Keri Graham who stripped to a skimpy outfit and writhed around show boss Simon Cowell. Also included was Arisxandra Libantino, aged 11, who sang the track "One Night Only".

Last year the programme was investigated by Ofcom after complaints over an appearance by burlesque dancer Beatrix Von Bourbon, but was cleared of breaching the broadcasting code.

This week's acts drew online criticism from some viewers. One wrote on Twitter: "Nice family viewing as your child asks 'Mummy why has that lady got hardly any clothes on, and what is she doing with those men?'."

And best-selling writer Jojo Moyes said: "I hate that lapdancer moves are somehow considered family entertainment."

ITV said the dance had been "carefully edited" to ensure it was suitable.

The launch of ITV show BGT peaked at an audience of 13 million viewers, while the BBC1 singing contest drew 7.7 million at its height for its third programme.

The first round in the ratings war appeared to justify ITV's decision to schedule its show earlier than usual to go almost head-to-head with its rival as its 10.5 million average audience made it the highest rating show on British TV so far this year.

The figure - which includes viewers of its +1 catch-up channel - was also up on the debut show for the 2012 series which drew 9.9 million.

The BBC could draw some comfort from its 6.7 million average being the highest so far this series. It has already shied away from a further clash by scheduling next week's edition of The Voice 95 minutes later, starting at 8.20pm, saying it was in the best interest of viewers, some of whom want to watch both shows.

ITV's director of television Peter Fincham said he had been "delighted with such a strong start".

A BBC source congratulated ITV on a strong night, but said they were also pleased The Voice continued to build its audience.

PA