President Trump, Melania, Queen Elizabeth and Kate Middleton at the Royal Palace

Here's more, from the USA Today:

President Donald Trump has left no doubt over the years that he is a big fan of Queen Elizabeth II, so when she hosted a 70th anniversary reception at Buckingham Palace Tuesday evening for NATO leaders, the president and first lady Melania Trump were there to mingle.

For the NATO reception, the dress code was cocktail attire, and cameras caught what the Trumps were wearing when they arrived at the palace: Melania Trump was in a buttercup-yellow coat by Valentino with an ankle-length cape dropping from her shoulders, over a magenta-colored dress and matching magenta spike heels. 

The president wore a dark business suit with a royal-blue tie. 

Despite their current embarrassment over sex allegations against Prince Andrew, the royal turnout for the reception was impressive, starting with the future king, Prince Charles, and his wife, Duchess Camilla of Cornwall.

The Prince of Wales, 71, is taking an ever more prominent role in high-level occasions now that his father, Prince Philip, 98, has retired, and his mother moves further into her 10th decade.

Earlier on Tuesday, he and Camilla, wearing a bright red dress, hosted the Trumps for tea at Clarence House, the second time the president and first lady met the royal heirat his London residence. 

The queen, who also held three audiences earlier on Monday to receive diplomats from two countries and also NATO Secretary General Jens Stoltenberg, was wearing a cream-colored dress with pearls and a large diamond sunburst broochat these earlier meetings. 

For the reception, she changed into a different dress in a swirly teal pattern with her diamond-studded Palm Leaf brooch anchoring a scarf on her shoulder. She carried her ever-present black handbag on her arm and wore black gloves for greeting guests.

Charles' daughter-in-law, Duchess Kate of Cambridge, 37, was also present at the palace reception but without her husband, Prince William. According to a post on Twitter, she was dressed in a green dress.

William, 37, the second in line to the throne, is on a four-day official visit to Kuwaitand Oman as he, too, takes on more responsibility representing his grandmother and Britain abroad.

Even more interesting is who wasn't there from the royal family: Prince Andrew, the Duke of York, 59, the queen's second son, who ordinarily would be present for such a reception.

But Andrew stepped away from all royal duties two weeks ago after an interview he did with the BBCwas widely attacked for failing to adequately explain his longtime relationship with American convicted sex offender Jeffrey Epstein and whether he had sex with a 17-year-old two decades ago.