Princess Diana's nieces Lady Amelia and Lady Eliza Spencer caught the eyes of onlookers on the third day of Royal Ascot.

The twin sisters stunned in baby pink dresses as they attended Ladies Day on Thursday. 

Amelia and Eliza, both 33, were pictured at the famous horse racing event together wearing Holland Cooper with matching white shoes and handbags. 

One wore a white hat while the other wore a pink one, matching her dress. 

The twins were among other members of the Royal Family and celebrities to have appeared at the racecourse. 

Their appearance on Ladies Day comes after the sisters made a striking entrance at this year's Royal Academy Summer Exhibition preview party last week. 

Amelia and Eliza wore daring black and red ensembles, with Amelia opting for a black mini dress featuring long sleeves and a ruched skirt.  

Eliza, meanwhile, wore a full-length scarlet gown with a fitted silhouette, open back and high back slit as she stepped out at the glamorous occasion at Burlington House.

Both sisters, the twin daughters of Charles, 9th Earl Spencer, and Victoria Aitken, completed their looks with smoky eye make-up and wore their blonde hair in loose waves.

The pair were also seen earlier this month looking glamourous for London Air Ambulance's star-studded charity gala.

The socialite twins, both 33, exuded sophistication and glamour as they stunned in floor-length gowns for the prestigious event, which sought to celebrate the incredible work of the London-based charity. 

Lady Eliza opted for a striking black floor lace gown and accessorised with a diamond necklace and simple handbag.

Meanwhile, Lady Amelia's show-stopping dress was dominated by glistening diamonds, accompanied by a matching purse and necklace.

The two sisters both wore their long tresses down, and beamed as they posed for photographers at London's elegant OWO hotel.

They put on brave faces as they were also spotted at the Cannes Film Festival in France in May as they oozed glamour.  

And Amelia and Eliza stepped out for a party on the opening day of the Chelsea Flower Show in affordable high street heels and handbags. 

Among the other members of the Royal Family to appear at Ascot were Carole Middleton and the Duke and Duchess of Edinburgh.  

Prince Edward and Sophie attended the star-studded event the day before their 27th wedding anniversary, with the Duchess of Edinburgh wearing the same pearl necklace she was married in.

The couple dressed for the occasion with Prince Edward in a top hat and Sophie in a navy blue dress with a matching hat.

The Duchess of Edinburgh rode in the second royal carriage during the Ascot Procession alongside Princess Anne.

She was later spotted in the royal box laughing and chatting with her husband, Princess Anne and Zara Tindall.

No one had a better time on the track than the Princess of Wales's mother, 71, who delivered race day glamour, held court in the Royal Box and reunited with senior members of The Firm - all in one day.

All eyes were on Carole on Wednesday as she arrived for day two of the prestigious British racing event alongside her rarely pictured daughter-in-law, Alizee Thevenet.

Dressed for the festival that is just as famous for its fashion as the racing, Carole repurposed the dress she wore for her daughter Pippa Middleton's wedding nine years ago in a sartorial twist that left royal fans delighted.

She repurposed the blush pink Catherine Walker ensemble for a day out at the races in Berkshire.

Carole paired the designer dress with a matching hat and shoes, both from Emmy London, as well as £2,150 amethyst and diamond earrings from Kiki McDonough - one of Catherine's favourite brands.

When she joined the Princess of Wales in the Royal Box, Carole couldn't help but look adoringly at Catherine, who returned to Ascot after a two-year absence due to her cancer diagnosis and treatment.

Photos showed Catherine holding the door open for her mother before the pair were seen holding hands, whispering to each other and enjoying what appeared to be an animated catch-up.

As the races got underway, Carole settled in for an action-packed afternoon with a beverage as footage showed her cheering for the horses and chatting with Prince William's childhood friend and Princess Charlotte's godfather Thomas van Straubenzee.

Other famous faces in the Royal Box yesterday included Sir Gareth Southgate, Princess Anne and Lady Sarah Chatto, whose friendship with Carole was on full display.

Princess Margaret's daughter was seen smiling at Carole during a rare candid moment, as it appeared Prince William's mother-in-law has firmly cemented her status as a royal insider.   

Inside the Royal Box, Carole joined King Charles, 77, and Queen Camilla, 78, as well as the Prince and Princess of Wales, the Duke and Duchess of Edinburgh, and the Princess Royal - who recycled a 25-year-old pink dress for the occasion - to watch the races. 

Among the famous faces to have also been spotted at Ascot on Ladies Day was Hollywood star Stanley Tucci, 65, who is a regular at royal events and dinner parties. 

He looked just as comfortable in a landau as he travelled to the Berkshire racecourse alongside his wife, Felicity Blunt. 

The American actor dressed for the part as he opted for a black top hat with an impeccably tailored suit.  

Meanwhile, the sister of Tucci's The Devil Wears Prada co-star, Oscar nominee Emily Blunt, put on a stylish display in a floral dress for the most popular day of the festival, when racegoers pull out all the fashion stops.

Another famous face making their debut in the Royal Family's Ascot procession was the Earl Snowdon's long-term girlfriend, Isabelle de La Bruyere, as the pair had the honour of riding alongside King Charles and Queen Camilla.