The Alfie star has been dating fellow actor Tom Sturridge since early 2011, and they're set to become parents later this year (12), reports Us Weekly.
Editors at the magazine claim the couple announced the news to loved ones over the Christmas (11) period.
A source tells the publication, "(Their friends) were not surprised by the news of the pregnancy. They're really good together.
"They just spent the holidays in Paris together after they announced the news in London."
A representative for Sturridge refused to confirm or deny the report, telling the magazine, "We don't comment on our client's personal lives (sic) at all."