India's three-time prime minister Vajpayee dies aged 93

Then Indian Prime Minister Atal Behari Vajpayee pictured during a function at his residence in New Delhi on June 1, 1999

Three-time Indian prime minister Atal Bihari Vajpayee has died, current leader Narendra Modi said Thursday of the ailing 93-year-old who had been hospitalised.

"Atal Ji's passing away is a personal and irreplaceable loss for me," Modi said in a tweet Thursday, using a Hindi-language honorific.

"It was Atal Ji's exemplary leadership that set the foundations for a strong, prosperous and inclusive India in the 21st century."

Vajpayee had battled poor health for years but his condition deteriorated sharply in recent days.

The former premier was being treated at the All India Institute of Medical Sciences (AIIMS) in Delhi, where he was admitted nine weeks ago with health complications.

"Unfortunately, his condition deteriorated over the last 36 hours and he was put on life support systems. Despite the best efforts, we have lost him today," AIIMS said in a statement.

"We join the nation in deeply mourning this great loss."

His waning health sparked a flurry of visits from top dignitaries Thursday, including Modi and senior cabinet ministers.

Vajpayee, a former journalist and poet-turned-politician, was credited with helping lay the foundations for the meteoric rise of the Bharatiya Janata Party (BJP), the right-wing political powerhouse that rules India today.