Patrick Thelwell, 23, (pictured) was found guilty of a Section 4 public order offence last month after he threw eggs at the King and Queen Consort. He will be protesting the Coronation on Saturday.
Graham Smith, CEO of Republic, said at an republican speaker event in West Kilburn in London on Wednesday night that the group will continue to protest the King even after the coronation.
EXCLUSIVE: Republic, a group that wants to see the monarchy abolished and the King replaced with an elected, democratic head of state, has planned a demonstration in London on May 6.
A group of demonstrators held banners calling for a Welsh Republic during King Charles and Camilla s visit to Cardiff although the protesters were outnumbered by well-wishers.