The Duke and Duchess of Cambridge will have a meeting and lunch with India's prime minister Narendra Modi as their official tour of the country continues.
William and Kate will sit down for informal talks with the Indian premier in New Delhi's Hyderabad House, a former royal residence of Maharajas that has hosted heads of state from across the globe.
The Cambridges' official tour of India was announced after Mr Modi had lunch with the Queen during his visit to the UK in January.
The Duke and Duchess are on a seven-day tour of India and neighbouring Bhutan, their first visit to both countries.
On Monday at a special garden party celebrating the Queen's 90th birthday, which falls next week, William paid tribute to his grandmother, describing her as a "wonderful great-grandmother'' for his children and very much his "boss''.
The Duke also said she was a "guiding force'' for her family.
The royal couple will later travel to Kaziranga National Park in the state of Assam, where over the next few days they will learn about the people and wildlife who inhabit the area.
Kaziranga is a World Heritage Site and a wildlife conservation area of great global importance.
It is home to elephants, water buffalo, the endangered swamp deer, tigers, and two-thirds of the world's population of Indian one-horned rhinoceroses.
The visit coincides with the Bohag Bihu festival, the celebration of the Assamese new year, and in the evening around a campfire, the Duke and Duchess will meet local people and see dances and musical performances.