Naomi Watts and Liev Schreiber want to get married.

The couple, who have sons Alexander, six, and Samuel, five, have been together for nine years and are considering taking their relationship to the next level by tying the knot. "While Naomi and Liev have had their ups and downs, including a cancelled New Year's Eve wedding right before 2008, they've finally worked out their differences and are rethinking marriage," a source said.

The pair reportedly grew closer after Naomi, 45, was heavily criticized for playing the late Princess Diana in her biopic, which was a flop at the box office, last year. "Liev really admired how Naomi rose above the flak she got for Diana - a role he really thought she'd win awards for. She was totally broken-hearted over that movie and Liev has played a huge role in getting her confidence back so she could carry on with four more films she has in production," a source said.

Meanwhile, the blonde beauty recently admitted she was instantly attracted to the hunk when she met him at the Metropolitan Museum of Art's Costume Institute Gala in 2005 and she couldn't possibly let him slip away. "I was wildly attracted to him and his work, so I said something cheeky as he was about to walk out. I said, 'Don't you want my digits?' Because I couldn't possibly say, 'Would you like my phone number?' It made him laugh. He texted me five minutes later saying, 'Would you like to go for a drink now?' And I said, 'No, I'll meet you for breakfast tomorrow,'" she said previously.