John Souttar: Rangers sign Hearts defender on pre-contract agreement
The Scotland international is out of contract this summer and was also wanted by several English Championship clubs including Blackburn Rovers.
However, after initial talks with Rangers, Souttar has agreed to join the Scottish Premiership champions.
Sky Sports News understands the 25-year-old is keen on a permanent move to take place this month.
Souttar has made over 150 appearances for the Tynecastle Park club, six years after joining from Dundee United.
Following several serious injuries, Souttar has played all but two Premiership games this season and his impressive performances saw him earn a Scotland recall.
Rangers' sporting director Ross Wilson told the club's official website: "We are really looking forward to John joining Rangers and continuing his development under Gio, our coaching and support staff.
"John is a full Scotland international and has so much potential ahead for the coming years. I have really enjoyed getting to know John across all of our conversations so far and I can see how excited he and his family are to be joining Rangers. We are equally excited to welcome John to Ibrox."
Reacting to the announcement, Hearts issued a statement saying they want Souttar to remain at Tynecastle until the end of his deal.
"The club reiterates that John is an important member of the first-team squad and will remain so until the end of the season unless a significant and satisfactory offer is made during the January transfer window."
• Who will win the Premiership title?
• Can Hearts hold off rivals for third?
What will Souttar bring to Rangers?
Souttar's ability to lead by example and be an imposing figure on the pitch is there for all to see.
Going back to Hearts' first Premiership match of the season, the defender helped his side at both ends of the pitch as they beat Celtic 2-1.
Some brave blocks, well-timed tackles and the ability to guide his fellow defenders through the match was impressive - just as his desire to get on the end of a cross to head home an 89th-minute winner.
That presence in an attacking sense will excite Rangers fans, and dead-ball specialists James Tavernier and Borna Barisic.
Wilson has often spoken about the need to be forward-thinking around recruitment and this move also demonstrates the club are continuing to progress in this area.
With uncertainty about Connor Goldson's future - who is yet to agree a new deal beyond the end of this season - Souttar could replace the Englishman.
The Ibrox club are top of the Premiership by six points but this move shows they are already planning for the future under Giovanni van Bronckhorst.