The 24 year old, signed from Mansfield Town in 2004, recently earned a call-up to the Republic of Ireland squad, led by Steve Staunton.
Lawrence cost Sunderland £175,000 which has since risen to £325,000 following promotion to the Premiership. An extra £50,000 will be owed if Lawrence plays for the R.O.I.
Meanwhile, ex-Sunderland midfielder, Martin Woods, has joined Rotherham United after being controversially released by the Black Cats.