Chief Minister Devendra Fadnavis and Uddhav Thackeray traveled together on a Mumbai to Nagpur flight.
The BJP dismissed any political significance, describing the meeting as coincidental and highlighting cordial personal relations.
Uddhav Thackeray was accompanied by Aaditya Thackeray and Rajya Sabha member Sanjay Raut during the journey.
BJP and Shiv Sena (UBT) leaders downplayed rumors of political realignment following the recent defection of Lok Sabha MPs.