The pictures follow Markle's official meet-up with Harry's extended family at the annual pre-Christmas lunch at Buckingham Palace hosted by his grandmother Queen Elizabeth II.
Prince William and his bride Kate Middleton were bestowed with the titles Duke and Duchess of Cambridge on the day of their wedding in April 2011.
Kensington Palace confirmed that formal invitations have been sent by the Prince of Wales, for the May 19 service at St George's Chapel, Windsor.
The announcement comes three weeks after the couple confirmed their engagement last month and said the ceremony would take place at St George's Chapel in Windsor Castle.
'What is the purpose of your visit?' the immigration officer at London Heathrow asked Deborah Das.
The announcement came a day after royal bride-to-be Markle on Thursday confirmed that her ailing father will not attend her wedding with Prince Harry in Windsor Castle.