KIEV, Ukraine - The Chernobyl nuclear power plant will open again soon - for tourists.

Beginning next year, Ukraine plans to open up the sealed zone around the Chernobyl reactor to visitors who wish to learn more about the nuclear disaster that occurred nearly a quarter of a century ago, the Emergency Situations Ministry said Monday.

Chernobyl's Reactor No. 4 exploded April 26, 1986, spewing radiation over a wide swath of northern Europe. Hundreds of thousands of people were resettled from areas contaminated with radiation fallout in Ukraine, Belarus, and Russia. Health problems linked to the accident persist.

The so-called exclusion zone, a highly contaminated area within a 30-mile radius of the exploded reactor, was evacuated and sealed off after the explosion. All visits were prohibited.

Today, 2,500 employees maintain the remains of the now-closed nuclear plant, working in shifts to minimize their exposure to radiation.

Several hundred evacuees have returned to their villages in the area despite a government ban. A few firms offer tours to the restricted area, but the government says those tours are illegal and safety is not guaranteed.

Emergency Situations Ministry spokeswoman Yulia Yershova said experts were developing travel routes that would be both medically safe and informative for visitors. She did not give a date when the tours would begin.

"There are things to see there if one follows the official route and doesn't stray away from the group," Yershova said. "Though it is a very sad story."

Helen Clark, chief of the U.N. Development Program, toured the plant Sunday and said she supported the plan because it could help raise money and tell an important lesson about nuclear safety.

"Personally I think there is an opportunity to tell a story here, and of course the process of telling a story, even a sad story, is something that is positive in economic terms and positive in conveying very important messages," Clark's office quoted her as saying.

The ministry also said Monday it hoped to finish building a new, safer shell for the exploded reactor by 2015. The new cap will cover the original iron-and-concrete structure that was built in haste over the reactor. It has been cracking, leaking radiation, and threatening to collapse.

The new shell - 345 feet tall, 853 feet wide, 490 feet long, and weighing 20,000 tons - will be slid over the old shelter. It will be big enough to contain the Statue of Liberty.

The cost of the project, financed by international donors, has risen from $505 million to $1.15 billion because of stricter safety requirements, Ukrainian officials said.