Charles received delegations from both Houses of Parliament at his royal residence as part of his milestone birthday celebrations.
Mrs May smiled as she greeted the heir to the throne despite the Prime Minister’s ongoing fight to save her unpopular Brexit deal.
Labour leader Jeremy Corbyn, who has slammed Mrs May’s Brexit blueprint, also attended the Parliament birthday bash.
And House of Commons speaker John Bercow, Commons leader Andrea Leadsom and leader of the House of Lords Baroness Evans were among those at the event.
The group posed for a picture against the stunning backdrop of Charles’s grand residence to mark the occasion.
Charles’s meeting with politicians at Clarence House was the latest birthday event for the Prince, who turned 70 yesterday.
Last night, the Queen hosted a spectacular birthday party for her son at Buckingham Palace.
Charles looked smart in a bow tie, while his wife Camilla, Duchess of Cornwall, was elegant in a Bruce Oldfield gown and dazzling jewellery.
Prince Charles met Theresa May at Clarence House today (Image: PA)