Karnataka Chief Minister B S Yeddyurappa, who struck a defiant note and cancelled his visit to Delhi last night, has been summoned this morning amid strong indications that BJP may ask him to step down.The Chief Minister, who is facing allegations of corruption and nepotism, dropped his plans to fly to Delhi in the evening for a meeting with BJP president Nitin Gadkari who was authorised to take a decision on Karnataka.Top BJP leaders including Arun Jaitley, Ananth Kumar and BJP General Secretary (Organization) Ramlal met with Gadkari late in the night when it was decided to summon him in the morning following his cancelling the visit.Earlier, after meeting senior leaders L K Advani, Murli Manohar Joshi, Rajnath Singh and Sushma Swaraj on Sunday morning, Mr Gadkari said, he will discuss the issue again with Yeddyurappa before taking a decision.Sources said there was a feeling in the meeting that it was becoming increasingly untenable for Yeddyurappa to continue in office at a time when the party is carrying on a campaign at the national level on the telecom scam.They added what seemed to have tilted the leaders' thinking were fresh media reports that talked of cheque transactions to the tune of 20 crore rupees being allegedly transferred to CM's sons and son-in-law from a Bellary mining company.