Justin Timberlake and Jessica Biel's relationship isn't as rosy as they would have everyone believe, according to the latest reports.

The couple - who recently moved into an apartment in New York together - are allegedly going through a rough patch that could possibly lead to their break up, says a U.S. publication.

A friend of Jessica's tells the Chicago Sun Times, "Things are not going as smoothly as [Biel and Timberlake] would want people to think they are".

While a close pal of Justin says, "I can always sense when Justin is beginning to get itchy in a relationship. ...While he's still very public about being seen with Jessica, it's interesting. ...He hardly talks about her when she's not around.

"The same thing happened with Cameron [Diaz], and it also was the case with Britney [Spears].”

The couple did nothing to dispel the gathering split rumours when they failed to turn up to a scheduled promotional appearance at the launch of an Indiana Live Casino in Shelbyville, Indiana, on March 13.

Justin dated Cameron for three years before moving onto Jessica, while his sweetheart Britney was his first high-profile romance, lasting almost five years.

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