NEW DELHI — Arun Jaitley, who as finance minister of India under Prime Minister Narendra Modi oversaw some of the country’s boldest economic experiments and earned respect and trust across a fractured political landscape, died here on Saturday. He was 66.

The All India Institute of Medical Science announced his death there in a brief statement, without specifying the cause. Mr. Jaitley had been ill for several years.

A lawyer by training, Mr. Jaitley was a versatile member of the Hindu nationalist Bharatiya Janata Party, known as the B.J.P., and served senior roles in India’s finance, defense and law ministries. As finance minister during Mr. Modi’s first term, he presided over the invalidation of nearly all of India’s paper currency in 2016, a sweeping if ultimately unsuccessful attempt to crack down on illegal cash transactions.

He cultivated a reputation for openness. As the party’s leadership pinched off the news media’s access to the government, Mr. Jaitley continued to grant interviews to journalists, though some said he traded tips for favorable coverage. He ingratiated himself with varied sections of India’s intelligentsia and befriended strangers during morning walks in Lodhi Garden, a park of crumbling medieval tombs in central Delhi.