Chief Ministers of West Bengal, Bihar, Chhattisgarh and Jharkhand, Mamata Banerjee, Nitish Kumar, Raman Singh and Raghubar Das were among senior political leaders who today visited the All India Institute Of Medical Sciences (AIIMS) where former prime minister Atal Bihari Vajpayee is undergoing treatment, hospital sources said.

Union minister Ravi Shankar Prasad also went to the All India Institute of Medical Sciences, they said.

The four chief ministers are in New Delhi to attend a meeting of the NITI Aayog which will be presided over by Prime Minister Narendra Modi.

According to AIIMS sources, Mr Vajpayee's condition is improving even though he continues to be in the Intensive Care Unit of the Cardio-Thoracic Centre at the hospital.

"Former Prime Minister Atal Bihari Vajpayee is stable. He continues to show improvement and is being monitored by the team of doctors," the AIIMS said in a statement yesterday.

Mr Vajpayee was admitted to the premier hospital on June 11 with a kidney tract infection, chest congestion and low urine output.He was immediately evaluated by a team of doctors and put on injectable antibiotics.

Mr Vajpayee, a diabetic, has one functional kidney. He had suffered a stroke in 2009 that had weakened his cognitive abilities. Subsequently, he had developed dementia.

Prime Minister Narendra Modi, BJP chief Amit Shah, RSS chief Mohan Bhagwat, former prime ministers Manmohan Singh and HD Deve Gowda, Rajasthan Chief Minister Vasundhara Raje and Congress president Rahul Gandhi have visited the AIIMS since the BJP stalwart was admitted there.Vajpayee was thrice elected the prime minister between 1996 and 1999. He is the only non-Congress prime minister to have completed the full term of five years, from 1999 to 2004.As his health deteriorated, he slowly withdrew himself from public life and has remained confined to his residence here for years now.

PTI