Rachel Riley flaunts her long legs in a red silk gown with a sexy thigh-high split

She's been a lifelong supporter of Manchester United.

And Rachel Riley was naturally the guest of honour at the team's annual United for Unicef Gala Dinner, leading a host of famous sportsmen and their glamorous partners as she made her way down the red carpet.

The Countdown presenter looked incredible in a bright red silk dress featuring a sexy thigh-high split as she arrived at Old Trafford on Wednesday night.

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Doing her best Angelina Jolie impersonation, Rachel ensured her long legs were on display in the elegant gown, posing like a pro as she made her way into the venue.

The classy garment boasted long sleeves and a plunging neckline, and was set off with a simple pair of black heels.

She carried a small studded clutch bag in one hand and completed her look with dazzling jewels.

Rachel wore her blonde locks pulled back in a bun, with loose tendrils of hair framing her face.

Also in attendance at the event were the likes of Manchester United manager Jose Mourinho.

The dinner celebrated 18 years of the partnership between Manchester United and Unicef, the worldís leading childrenís organisation, and raised funds for its crucial work for vulnerable children around the world

The annual event has helped to raise over £4million for Unicef so far, and all funds from this year's dinner year’s dinner will go towards Unicef’s vital work in Thailand, to support education programmes for children with limited or no access to schooling.

Mourinho said: 'Charity is one of the amazing things in society and I have always been very supportive of Unicef.

'You know that the money is going to the right place and is going to make a big difference.

'This year, the money is going to help children in Thailand so we know that we are going to contribute to a better future – I think it is difficult to have a better feeling than that.'

Lifelong United fan Stormzy will be performing his new single Blinded By Your Grace at the event.

Unicef UK Deputy Executive Director, Catherine Cottrell, said: 'Over the last 18 years, Manchester United has helped Unicef transform lives and keep children safe across the world.

'We are very proud of our long-standing United for Unicef partnership and want to thank the club and its fans for their continued support.'