(Jan. 29) -- As a result of the death of her one-time fiance Heath Ledger, production of the Michelle Williams movie "Blue Valentine" has been put on hold.

PEOPLE reports that the film will be on hiatus "until she is ready," according to a "Valentine" insider. The movie was set to begin filming on February 25.

"We're hoping she will still come back and do the film and are happy to wait," the source told PEOPLE.

"Valentine," which also co-stars Ryan Gosling, is a drama about the relationship between a a newly-married young couple.

"The film is tailor made for those two so of course we would want to wait. You can't get much better than them," the source said.

Williams and Ledger met on the set of "Brokeback Mountain," and quickly formed a romantic relationship. They had a daughter, Matilda, together, and were engaged to be married before ending their relationship.

Williams had just wrapped up her last scene in the film "Mammuth" in Sweden when she received the news of Ledger's death.