The duo picked up the 'Best Performance' gongs at the event, which was held in New York last night (November 21).
Eccleston beat Brazilian actor Fábio Assunção, South Korea's Jang Hyuk and Sweden's Michael Nyqvist - from the popular Millennium - to take home the prize for his role in BBC One's Accused.
Walters beat Nygvist's co-star Noomi Rapace as well as Hong Kong's Athena Chu Yan and Assunção's colleague Adriana Esteves to win the award for her portrayal of Mo Mowlam in Channel 4's Mo.
Mo was also nominated in the 'Mini-Series' category, but was beaten by Millennium.
Other British winners included Gareth Malone, who won the prize for arts programming for Gareth Malone Goes to Glyndebourne, beating shows from Brazil, Germany and Japan.
Elsewhere, Accused scooped the prize for 'Best Drama Series', triumphing over France's Engrenages, which is shown in the UK as Spiral. Japan's Sakanoue no Kumo and Brazil's Under The Law rounded out the nominees.
The World's Strictest Parents also took home a prize, winning the 'Non-Scripted Entertainment' category.
However, Channel 4's Facejacker lost out in the 'Best Comedy' category to Belgium's Benidorm B**tards and Sky News's Inside The Taliban was beaten by a Brazilian piece about the war on drugs in the 'News' category.
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