PROVIDENCE — The ferry operator that runs service between Narragansett and Block Island plans to launch new high-speed service to the island from Fall River, Mass., officials said Monday.Fall River Mayor William Flanagan said the daily service provided by Interstate Navigation Co. is expected to launch in June. He said the ferry will stop first in Newport and continue on to Block Island.There will initially be just one departure from Fall River a day, but Flanagan said the service could expand if there is greater demand.He said he hopes the ferry will attract users from the greater Providence area as well as from in and around Boston, New Bedford and Worcester.“It’s an experience — Block Island and Newport are fun places to be,” Flanagan said, adding that he hopes travelers will dine in Fall River before or after they take the ferry.With the high-speed service, the trip from Fall River to Newport will take about 45 minutes, he said. Current high-speed ferry service from Newport to Block Island takes just over an hour.Ticket prices aren’t set yet but Flanagan said the service would be cost-effective when compared to driving and parking in Newport, or driving to Narragansett to get the existing ferry.Interstate Navigation, of New London, Conn., currently provides year-round service to Block Island from Point Judith. The company carried 200,000 round-trip passengers in the 2012 fiscal year, the vast majority during the summer season.Another ferry operator, Rhode Island Fast Ferry, is seeking to add service to Block Island from Quonset in North Kingstown. Interstate opposes the plan, saying the competition will siphon off business and force it to hike rates or reduce service.That, in turn, will have a “dramatic negative impact” on residents and businesses on Block Island by driving up the cost of food, fuel and other goods, Interstate said in filings with the state last month.Rhode Island Fast Ferry currently offers service from Quonset to Martha’s Vineyard.