The actress, who left the show at the end of the recent fourth season finale, told Doctor Who Magazine: "I knew that there would definitely be an end to Donna, at the end of the series.
"But had that not been the case, had it been open-ended, had there been potential for Donna to stay on for another series, I must confess that I'd have said 'yes' like a shot."
Despite Donna's mind being wiped in 'Journey's End', Tate added: "Could Donna come back? Well, in science fiction, anything is possible."
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