The 31-year-old, who won the title in 2013, has competed in the BTCC since 2008 and has raced for the West Surrey Racing-run BMW UK team for the past three seasons. Jordan was in contention for the title until the final race of last season, finishing just two points behind team-mate Colin Turkington in the final standings.
Due to the coronavirus pandemic, this year’s BTCC is scheduled to start at Donington Park on 2 August and will feature nine events and 27 races in just 16 weeks.
Neither Jordan nor WSR has given an exact reason for his departure.
In a statement, Jordan said: “As I’m sure many of you can attest to, the current climate has impacted all of us more than we could ever have anticipated. Unfortunately, this has placed me in a position where my head had to overrule my heart, and the tough decision was made to not compete this season.”
Jordan added that he is going to “take stock and plan what our new future looks like.”
WSR boss Dick Bennetts said: “AJ has made a huge contribution to our BTCC success since 2017 – coming so close to winning last year’s title – and we’re sorry to be losing him.”
Jordan has won 26 races and was backed by Pirtek for the bulk of his BTCC career, with his 3 Series running under the BMW Pirtek Racing banner last year. But when the firm withdrew its sponsorship for 2020, his seat had been in doubt, until he had secured a deal to stay with the squad in a third Team BMW-badged car.
Jordan’s withdrawal shortly before the start of the season creates an open seat at the title-winning WSR team. There is no news yet whether the team intends to sign a replacement drive for this year or continue with two cars for Turkington and Tom Oliphant.