According to Alan Nixon, it will take up to £4 million for the Championship side to part ways with their head coach.
McKenna oversaw promotion to the Championship last season with a second place finish in League One.
The 37-year-old is now leading the charge for another promotion battle this year, with the Tractor Boys currently second in the table in the second division.
This has led to some speculation linking him with a move to the Premier League, with Crystal Palace reportedly eyeing the Ipswich boss as a potential replacement for Roy Hodgson.
Carlton Palmer believes that McKenna has no reason to walk away from Ipswich at this moment in time, due to the legendary status he can achieve with Premier League promotion.
He also believes that Ipswich have done well to back the former Manchester United coach, who should repay their faith in him by committing his future to the club.
“Ipswich Town have moved quickly to try and negate Premier League club interest for their manager Kieran [McKenna],” Palmer told Football League World.
“The club have put a £4 million clause on the manager amid interest from Premier League clubs, Crystal Palace and others.
“The Americans have also given Kieran a good salary, believed to be in the region of about £25,000-a-week to keep him happy.
“Ipswich are on a fabulous run in the Championship, five wins in six games, already 10 points clear of sixth place Birmingham City, occupying that last Championship play-off spot.
“Two points behind the leaders [Leicester] City.
“For the life of me, it would have to take some unbelievable offer to leave Ipswich at this juncture.
“He’s looking at doing back-to-back promotions, he has the backing of the owners.
“He will be a legend in Ipswich for years to come, and what a great achievement.”
