Bartomeu and the rest of the Barcelona board resigned on Tuesday evening ahead of an expected vote of no confidence next month.
The 57-year-old's fate has perhaps been determined since he was heavily criticised by Gerard Pique and then Lionel Messi, who was furious that a summer exit from the Catalan club was blocked.
Bartomeu does not have much widespread support and was due to face a vote of no confidence in next month's election after the Spanish government gave the green light for voting to go ahead at the Nou Camp despite the coronavirus crisis.
As he announced his exit on Tuesday, Bartomeu also confirmed the "extraordinary news" that the outgoing Barca board had approved the club's participation in a future European Super League in order to safeguard Barca's future finances.
However, entry into any prospective European Super League - which has recently been discussed as a European Premier League - would be subject to approval by the club's members.
Additional reporting by PA.