ISTON – The mayor of Maine’s second-largest city predicted a major commercial development boom as a Rhode Island developer rolled out plans to open a big-box store on 40 acres near the turnpike.

“We’re at the brink of an economic development explosion within the city of Lewiston, and we commit to you this afternoon that our retail development recruitment will continue to be unwavering and unceasing,” Mayor Lionel Guay said at a City Hall news conference Thursday.

KGI Properties Inc., a real estate development company based in Providence, R.I., plans to open a big-box store on the parcel near the Maine Turnpike.

KGI, which has developed 2.5 million square feet of retail space throughout New England, is close to completing a deal with a major anchor retailer for the parcel, which sits directly across from the exit ramp of Exit 80.