Keri Russell and Matthew Rhys have been dating for two years now, and a report claimed that "The American" co-stars are allegedly engaged.

However, there is purportedly one thing coming between Keri Russell and Matthew Rhys' plans to get married - the "Felicity" star's marriage to her ex, Shane Deary, is yet to be finalized.

"Matthew asked Keri to marry him. However, it wasn't an immediate yes. She agreed to an unofficial engagement which made sense since Matthew and Keri are such private people," a source reportedly told Star Magazine, as reported by Celeb Dirty Laundry.

Despite being private, Matthew Rhys purportedly cannot keep his mouth closed about their "unofficial engagement."

"Everybody assumed they would have kept the news a secret until after they ran off to the courthouse, but Matthew's so happy he's having a hard time not telling just about everyone," the source added.

Is Matthew Rhys even making an effort to keep his relationship with his "The American" co-star hush-hush?

"If Rhys is trying to keep his romance with Russell private he's not doing a very good job of it," CDL wrote. "The couple was spotted out together earlier this month as they rode their bicycles around a Brooklyn, New York neighborhood, stopped for a beverage and appeared to share a few intimate moments."

"Neither Keri Russell nor Matthew Rhys is going to say much about their relationship, living arrangements or engagement anytime soon. She needs to put a legal end to her marriage to Deary before she can make any public acknowledgement that she is romantically involved with her 'The Americans' co-star."

Last March, Keri Russell celebrated her birthday in New York City with Matthew Rhys and her two kids, Willa and River.

"Willa and River are Keri's children from her six year marriage to carpenter Shane Deary," Daily Mail recounted. "A few months after the former couple announced the split in 2013, it emerged Keri and Matthew began dating."