Prince Philip, the husband of Queen Elizabeth Ii, officially opened the attraction's new $5.7 million (£3.6 million) Tiger Territory, which houses Sumatran tigers Jae Jae and Melati.
Zookeepers hope the pair will breed in a bid to give the critically endangered species a boost, and Halliwell was one of the first people to visit the creatures ahead of the enclosure's official opening on Friday (22Mar13).
The singer uploaded snaps on her Twitter.com page, writing, "Meet our tiger Jae Jae. Pussy cat, I love u (sic). In my next life I want to look after animals."