India's aviation regulator decided on Tuesday to allow Air India Ltd. to resume commercial flights on Boeing Co.'s 787 Dreamliner, nearly four months after it asked the flag carrier to ground its newest aircraft over safety concerns. The Directorate General of Civil Aviation in India grounded Air India's fleet of six Dreamliners in mid-January, matching an order by the U.S. Federal Aviation Administration after battery malfunctions on two 787s operated by Japanese carriers. India decided to lift its ban on Dreamliner flights after a briefing by Boeing executives about the successful installation of a new battery system on one of Air India's Dreamliners, an official in the civil-aviation ministry said. The Boeing team also informed the ministry of the modification plans for the remaining five 787 jets, the official said.

"We had a satisfactory presentation by Boeing," the official said. "After that, it was decided to issue an order to remove the grounding on Air India's Dreamliner fleet." The official said Boeing has told the ministry that it would modify the second 787 jet by the middle of May. Air India's six Dreamliners are expected to resume passenger flights by early June, the official said. A Boeing India spokeswoman declined to comment. On Friday, Civil Aviation Minister Ajit Singh said he expected Air India to resume commercial flights on the Dreamliners in mid-May, initially operating on domestic routes.