Jaitley, who had unexpectedly left for the US on January 13, has undergone tests for soft tissue cancer, sources said. Even during this time, he has been active on social media writing Facebook posts and tweeting about current issues.
66-year-old Jaitley had undergone a kidney transplant surgery on May 14, 2018, at AIIMS here and had not travelled abroad since then.
The Union Minister has undergone surgery at a hospital in New York on Tuesday, sources said.
He has been advised at least two weeks rest by the doctors, they added.
He was earlier this month named the publicity head of the BJP for the upcoming general elections.
With barely a week left for the 2019-20 Budget, the government Wednesday gave additional charge of Finance and Corporate Affairs portfolios to Railways and Coal Minister Piyush Goyal.
The Interim Budget for 2019-20 would be presented in Parliament on February 1.
Jaitley is now a minister without portfolio in the Narendra Modi government.
Earlier on May 14, 2018, when Jaitley underwent a renal surgery and was out of the finance ministry for nearly 100 days, Goyal was given additional charge of the finance ministry.
Jaitley had stopped attending office since the beginning of April 2018.
On August 23, 2018, Jaitley returned as Finance Minister and in the next few months, he had limited public interaction in order to ward off any infection.
He has been the Finance Minister in the Modi government right from the time it came to power in May 2014. He, however, was a minister without a portfolio between May 14, 2018, and August 23, 2018.
A Rajya Sabha MP since 2000, he was re-elected to the Upper House from Uttar Pradesh last year. He is also the leader of the House.