David Tutera, Ryan Jurica -- Twins From Split Have Never Met

The twins born more than a year ago to David Tutera and ex-partner Ryan Jurica have never met.

As TMZ previously reported, Tutera and Jurica each fertilized an egg that was implanted in the same surrogate, who gave birth to the two babies at the same time. David and Ryan split before birth ... David kept the girl, Cielo, and Ryan kept the boy, Cedric.

David -- who hosts CELEBrations on WE tv -- told Harvey and Charles on "TMZ Live" ... the kids have had zero contact because of the nuclear breakup.

Ryan tells TMZ ... he's attempted to create a relationship between the twins, but David would have none of it. Ryan says he thinks the kids need to establish a bond sooner than later, and, "I will do all that I can to foster it."

David hedged on "TMZ LIve," saying he's open to the kids connecting one day.