NEW DELHI (AP) — The Duke and Duchess of Cambridge have joined India's prime minister for a private lunch at a former palace in New Delhi.

Before going indoors, Prince William and his wife, the former Kate Middleton, strolled on either side of Prime Minister Narendra Modi on Tuesday.

They were seen chatting and smiling, before posing for cameras. Kate wore a full-sleeved gauze green dress, while William donned a blue suit and Modi was clad neck-to-toe in white.

The British royal couple are in India for a seven-day tour that also includes a trip to neighboring Bhutan. They've already visited Mumbai, and travel later Tuesday to a wildlife park in the northeast state of Assam that is home to rare, one-horned rhinos, tigers and other endangered animals.