Speaking to The Sun's TV Magazine, she said:
"[I'm] so very excited. Fifty years of Doctor Who and still going strong," she declared.
The actress went on to say: "It was amazing to see the response over in the US. The fans are mega-fans and its really rocketed in popularity over the past few years. I've been walking past the news stands in New York with Matt [Smith's] face gracing the covers of magazines.
"Steven [Moffat] texted me saying this will be something we will talk about in our dotage and he is right, we will. So watch this space!"
Speaking about The Doctors and Clara's relationship, she said:
"They are both as stubborn as each other and they challenge each other. It's almost more of a reluctant friendship," she explained.
"They are totally bemused by each other but are drawn together like magnets - they can't help liking each other but are constantly trying to work the other out."