Cameron joked that it was "tidy" to have Page at the St David's Day event and praised her work on the comedy series.
"There's no doubt in my mind that Wales has produced the finest sitcom to come out in the last five years: of course, Gavin & Stacey," said the PM.
"I think we have some of the cast here tonight, have we? Very good. Well, it's tidy to have you here."
He added: "I'm a huge fan. Like all sitcoms in the United Kingdom, it was much too short. We needed more episodes, but an absolutely fantastic piece of work and it gave pleasure to absolutely millions."
Cameron has previously revealed that he is a fan of music by The Smiths and that one of his favourite songs of all time is The Jam's 'Eton Rifles'.
Gavin & Stacey, which was created by James Corden and Ruth Jones, ended in 2010 after three series and Christmas specials.
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