Rangers' Kenny Miller
Warburton was appointed the Rangers manager in the summer of 2015, and the Englishman has a contract with the Gers until June 2018, according to Transfermarkt.co.uk.
Miller has spoken highly of Warburton, and believes that the Englishman committing his future to the Ibrox outfit would be the biggest signing of the summer for Rangers.
“I can’t speak highly enough of the job the manager has done,” Miller told The Glasgow Evening Times. “For me, if he can extend his contract then it would be the biggest signing of the season for us.
“Joey Barton - fantastic signing. A huge signing. But these guys are coming to Rangers off the back of the manager being here because of his influence when he’s met them.
“Of course, this football club is a huge attraction. I’ve said many times it doesn’t need to sell itself. But it takes someone with the manager’s vision and appetite to go and do what he’s done and it’s crucial for me that we keep him.”
Rangers manager Mark Warburton celebrates winning the Scottish Championship
Rangers won the Scottish Championship title last season and will feature in the Scottish Premiership during the 2016-17 campaign.
The Glasgow giants have been quite busy in the summer transfer window so far and have made a number of signings.
Former Newcastle United and Queens Park Rangers midfielder Joey Barton has moved to the Gers on a free transfer after leaving Premier League-bound Burnley.
Rangers manager Mark Warburton celebrates
Former QPR duo Niko Kranjcar and Clint Hill have also joined Warburton’s side, and so have Jordan Rossiter and Matt Gilks.
Josh Windass and Matt Crooks agreed pre-contract agreements with Rangers back in January.