The Queen could be celebrating a belated 90th birthday present at Royal Ascot this week.

Several horses carrying her purple, gold and scarlet colours have been entered for the world's most famous race meeting, including Dartmouth in the Hardwicke Stakes on Saturday.

The four-year-old won at the Berkshire course last July and has already won twice this season, at Chelmsford City and Chester, so will be bidding for a hat-trick.

Dartmouth is trained by Sir Michael Stoute and will be ridden by Ryan Moore - the same combination that won the Gold Cup for the Queen with Estimate in 2013.

That was the first time in the race's 207-year history that it had been won by a reigning monarch.

This year's renewal of the two and a half mile race is tomorrow (Thursday) at 4.20pm with its title being renamed the Gold Cup In Honour Of The Queen's 90th birthday.

Sir Michael is the most successful trainer at the Royal meeting, having gone into yesterday's opening day with 73 winners.

The Queen is not the only member of the Royal Family hoping for Ascot glory this week.

The Prince of Wales and Duchess of Cornwall own Carntop, who is due to run in the King Edward VII Stakes on Friday.

Saturday's card also includes The Wokingham Stakes, a six-furlong sprint which traditionally attracts a large field, so making it like a cavalry charge down the course.

Named after the town of Wokingham, this race has been held at the Royal meeting since 1813.

Most of this week is likely to see rain at the course.

Four millimetres fell over Monday night, taking the total rainfall past 30mm since Friday.

The going for the opening day on Tuesday was described as the softest at the Royal meeting for more than 40 years.

Following terror attacks in America, Paris and Brussels, the security at the course has been tightened considerably with armed police and sniffer dogs on site.