"I don't know why he does that but this is no way for a chief minister to behave, irrespective of his lack of experience," an official statement quoted Mr Singh as telling a TV channel.
No government can function in isolation, but Mr Kejriwal has completely isolated himself. AAP has completely lost ground in all states, he claimed.
"(Arvind) Kejriwal seemed to have apologised to (Bikram Singh) Majithia over drug charges possibly to prepare for next year's polls. But the fact was that things have turned worse for him," Mr Singh was quoted as saying in the statement.
On AAP's future prospect in Punjab, the chief minister claimed the party's MLAs were totally disappointed and were reportedly looking for alternatives in order to safeguard their own future.
On the TDP's decision to exit the ruling NDA a year before the Lok Sabha polls, Mr Singh claimed it showed the disenchantment in the ruling coalition and the prevailing mood of the nation, which was looking at a UPA sort of alliance as an alternative.
On Rahul Gandhi as the prospective prime minister, the Punjab chief minister said that he saw this to be an absolute possibility and that the Congress president would make a good PM.
The presence of a full and active crowd at the ongoing AICC plenary session also showed that people were looking up to Rahul Gandhi, Mr Singh said and ruled out any element of sycophancy in the response of the party members to Mr Gandhi's leadership.
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