An advertisement in the Royal Gazette on Sunday said people living in Chonburi, Ayutthaya and Chachoengsao provinces would not be allowed to go out unless necessary from Tuesday.
He added that a curfew will be imposed from 9 p.m. to 4 a.m., while checkpoints will be put in place to prevent people from traveling outside their provinces.
Bangkok and nine other provinces are already subject to these restrictions, the most severe for more than a year, since last Monday.
Thailand is currently struggling with its longest and most severe outbreak to date. The country reported 11,397 infections and 101 deaths on Sunday, bringing the cumulative total to 403,386 cases and 3,341 deaths.
Most deaths and infections in Thailand have been recorded since April, due to an outbreak fueled by the highly transmissible variants Alpha and Delta
The wave has engulfed hospitals, strained the economy and called into question plans to revive tourism.
In a bid to contain the outbreak, Thailand on Friday imposed a nationwide ban on public gatherings, with a maximum sentence of two years in prison or a fine of up to 40,000 Thai baht ($ 1,219.88) or both.
The deployment of vaccines in the country remains slow due to supply problems.
Only 5% of Thailand’s population have been fully immunized, and health officials said last week they would seek to impose limits on exports of the locally produced AstraZeneca vaccine because the country does not have enough for its own needs.