Justin & Jessica: Marriage Off The Table?

On-off-on couple Justin Timberlake and Jessica Biel are currently back together, a source close to the pair tells OK! — but only so long as she doesn't bring up the M word — Marriage.

According to the source, Justin first bolted a few months ago after his actress gal-pal asked him when he thought they might wed.

At 27, Jess would love to tie the knot. But Justin "is just not interested in getting married right now," partly because he has seen so many marriages fail, including that of his parents.

Jessica, a source says, "knows that if she and Justin are ever going to have a future, she has to be willing to be patient."