Major roadwork will be done on two congested Smithtown highways in the coming months, state officials announced Friday.

Officials say $4.3 million will be spent to repave 4.5 miles of Routes 25 and 25A. Route 25 will be resurfaced from Route 111 to Route 347, while Route 25A will be smoothed out from Lawrence Road to Route 25. Travelers have long complained of potholes and heavy traffic on the two roads.

Drivers are urged to slow down during the roadwork, and officials add traffic will get worse before it gets better. The state plans to have both roads repaved by July.