Metro Manila (CNN Philippines, March 13) — No tourists will be able to visit Boracay during a shutdown later this year, which may be set between June and September.

Tourism Undersecretary Ricky Alegre on Tuesday said the date range was recommended by tour operators and hotels because it was the lean season.

"We've seen the data — [visits] really [go] down. In fact, it's less foreign tourists during that time," said Alegre.

A more exact date is expected to be announced after the declaration of state of calamity in Boracay, which is scheduled to happen "before or after" Holy Week, or the last week of March.

Related: Duterte to declare state of calamity in Boracay

However, a shutdown for tourist bookings and hotels was "definite" and would push through, said Alegre. He, however, added the planned 60-day period is not enough.

Officials are in talks with airlines and hotels to waive rebooking charges or provide refunds for those who wish to cancel or move their trips.

The shutdown is intended for uninterrupted clean-up and rehabilitation efforts on the island.

This follows an ultimatum set by President Rodrigo Duterte, who gave Cabinet and local officials six months to clean up what he called a "cesspool" or he would permanently close Boracay.

Related: DILG: Six-month ultimatum on Boracay still stands

"Within that six-month period, we hope to have a time where we can do it faster. We're hoping the stakeholders will understand this," said Alegre.

The confirmation of the shutdown comes just ahead of an expected meeting of the inter-agency task force for Boracay on Thursday. The attendees include officials from the Departments of Environment and Natural Resources, Interior and Local Government, Justice, and Tourism. The meeting is expected to cover a new plan for the island, as planned by architect and urban planner Felino Palafox Jr.

The new plan will address the sewage problem, as the undersecretary said only 47 percent of 1,900 business establishments were connected to the sewage treatment plan.

As of March 2, the Interior Department said more than 800 establishments have committed violations since 2001.

Alegre also disclosed that Environment Secretary Roy Cimatu wanted to demolish structures on forestlands and wetlands — possibly including the mall.

Related: DENR: 5 of 9 Boracay wetlands damaged; 4 to be reclaimed

"He said in our meeting, we want to reclaim the forest land and the wetland," said Alegre. "If you are constructed on forest land, they will demolish you. If you are constructed on wet land, they will demolish you."

He added they were looking to dismantle structures between roads and the beach water.

"We're sorry, but if you're within that limit, you have to cut it. We'll have to take it out," said Alegre. "Besides, who gave the permit? Wala namang title iyon [Those don't have titles]."

Alegre appealed to tourists, particularly local travelers, to set their sights on alternative destinations.

"If you can rebook it to Bohol, Cebu, Siargao or Camiguin, why not? There's all these beaches from Bataan all the way to Pagudpud," said Alegre.

The Tourism Department is already kickstarting clean-up efforts in El Nido and Coron in Palawan, as well as Puerto Galera in Oriental Mindoro.

Watch The Source's full interview with Alegre here.