Sienna Miller looks back on her 2007 India trip with Amitabh Bachchan and Salman Khan

Hollywood actor Sienna Miller has opened up about a trip to India she made nearly two decades ago, and she says the memories are still vivid. In a recent interview, the 44-year-old spoke warmly about her 2007 stay in Mumbai and what it taught her about the country.

The visit was not a typical star tour. Miller did not come to promote a film or a show. She came as an ambassador for Global Cool, a group that campaigns on climate change. Over a week, she worked to raise awareness on the issue and to push for changes to Indian law, with the environment at the heart of the effort.

During the trip she went to several places, including Dharavi in Mumbai, often called Asia's largest slum. "I think India is the most incredible country, and I have been to many other places as well, apart from the slums in Mumbai," she said, adding that the goal was to get climate legislation changed.

Several big Bollywood names backed her cause along the way, among them Salman Khan and Amitabh Bachchan. Miller said she teamed up with lots of stars from the industry and described the whole experience as "a really enlightening trip".

She feels India has changed a great deal since then, and she makes no secret of her admiration. She pointed to its fast growing economy and said its film industry is bigger than any other in the world. "I loved the people that I met, and I would love to spend more time there," she said.

On the work front, Miller is now starring in War, a legal drama created by George Kay. She plays a Hollywood star caught in a very public divorce, with Dominic West as her estranged husband, a tech billionaire. Phoebe Fox, James McArdle, Pip Torrens, Nina Sosanya, Archie Renaux and Nick Mohammed complete the cast. The series premiered on HBO and HBO Max on October 1, and viewers in India can stream it on JioHotstar.