Navjot Singh Sidhu has resigned as Punjab Congress chief, in a stunning development just days after Amarinder Singh was replaced as Chief Minister in a series of events that had his approval.

The resignation, months before the Punjab election, has shocked the Congress leadership and is seen as a huge blow, given that the Gandhis were warned about appointing Mr. Sidhu as Punjab Congress chief. It was Priyanka Gandhi Vadra who had pushed for Mr. Sidhu, against all odds.

Sonia Gandhi and Rahul Gandhi are yet to reach Delhi after their visit to Shimla.

The surprise move comes at a time new Chief Minister Charanjit Singh Channi, seen to be close to Navjot Sidhu, had been making changes to the Punjab cabinet.

Though Mr. Sidhu was widely seen to act as “Super Chief Minister” in some of the decisions, he was reportedly not consulted or was ignored in recent top appointments that were seen as controversial.

Mr. Sidhu, say sources, was upset that these appointments and believed that they contradicted his pronouncements about fighting corruption. The double use of the word “compromise” in Mr. Sidhu’s resignation letter was seen as a clue to some unpleasant choices in the cabinet shuffle.

The resignation delivers a huge blow to the Congress, leaving it struggling for a face in Punjab ahead of polls, and also calls to question the decisions of Rahul Gandhi and Priyanka Gandhi. The party has been surprised on a day it was set to welcome prominent faces like Kanhaiya Kumar and Jignesh Mewani.

Earlier this month, Amarinder Singh resigned as Chief Minister, complaining of repeated “humiliation” by the party. Mr. Sidhu, who set the stage for his exit, has now himself quit his post, though he says he will “continue to serve the Congress”.

Mr. Sidhu’s move coincides with Amarinder Singh’s visit to Delhi today. Though it is described as “personal”, there is speculation about a possible meeting between the Captain and the BJP.