South Korea's maritime ministry said Thursday that it will start to hoist a passenger ship next month that sank two years ago and complete it before the end of July.

The 6,825-ton ship, the Sewol, sank off the country's southwestern coast on April 16 in 2014 while en route to the southern resort island of Jeju.

The accident killed 304 people, mostly high school students on a school excursion. Nine of them still remain missing.

The sunken ship will be pulled out of the water intact in order to keep any remains of people still missing from the tragic sinking, according to the Ministry of Oceans and Fisheries.

"We will recover the vessel without cutting the 145 meter-long ship as we do not want to lose any missing bodies believed to remain inside the ship," the ministry said in a release.

The 85.1 billion won ($72 million) project to recover the ship will be operated by a Chinese consortium led by China's state-run Shanghai Salvage.

Divers have closed all openings of the ship with nets to prevent any contents of the ship from slipping out.

They are now working on making the ship buoyant, by injecting air into the tanks in the vessel and installing some 30 large balloons and other floatation devices.

The ship will be on land before July unless there is unexpected inclement weather like a typhoon, the ministry said.

It will be the first time in world maritime history that a 145m vessel is elevated from the depths of 45m without dividing the body, according to the ministry.

The area where the sunken ship is submerged is notorious for fast currents and a muddy sea bed with poor visibility.

"The working conditions are tough, but we will do our best to complete the salvage safely and successfully," said Yeon Yeong-jin, deputy minister for marine policy office at the ministry. (Yonhap)