This year's Melbourne Cup will include a visit from a member of the royal family.

Zara Phillips, the Queen's oldest granddaughter, has been chosen as the official international guest of the spring racing calendar's biggest day of the year, News Limited newspapers say.

She'll be involved in presenting the Cup on November 3.

Ms Phillips is a cousin of Prince Harry and Prince William and is twelfth in line to the British throne.

She has enjoyed an equestrian career that nearly reached Olympic level when she was chosen to compete in the Beijing 2008 Olympic Games. She had to withdraw from the competition when her horse sustained an injury.

More than 100,000 people are expected to attend the Melbourne Cup at Flemington.