A delegation of Democratic Party of Korea lawmakers are heading to Japan for three days on Thursday ahead of the release of the wastewater stored at the earthquake-wrecked nuclear power plant in Fukushima.

“There are so many unaddressed questions surrounding the wastewater being dumped in the waters and South Korea can’t leave it up to the IAEA (International Atomic Energy Agency) alone,” Rep. Wi Seong-gon, part of the five-member delegation, told a press conference Wednesday.

He said that over the course of the trip the delegation planned to visit the Tokyo Electric Power Company headquarters and speak with residents living near the site of the nuclear disaster, evacuees and former workers of the plant.

“We are going to ask for more data to be published on radiation safety because what we have now is utterly insufficient,” he said.

He said that the governments of South Korea and Japan must make the safety of the people of both countries as a “top priority.”

“The governments must work together to determine if releasing the wastewater into sea is indeed safe, for not only South Korea and Japan but all surrounding countries,” he said. “Before we can determine the safety of the wastewater release, Japan shouldn’t expect South Korea to resume imports of Fukushima seafood.”

Rep. Yang Yi Won-young, also speaking at the press conference, said that as the opposition, the Democratic Party “couldn’t just idly sit by while the Yoon Suk Yeol administration does nothing.”

She said her party had suggested that the matter of wastewater release be discussed at Yoon’s summit with Japanese Prime Minister Fumio Kishida last month.

“But South Korea failed to touch upon it over the summit,” she said. “We’re going to let Japan know where South Korea stands on its plan to dispose of the wastewater from the plant.”

According to the lawmakers, the Democratic Party has not yet reached out to lawmakers of other countries about the Fukushima wastewater concerns.

The ruling People Power Party spokesperson Kim Min-soo said in a statement that the Democratic Party lawmakers’ Japan trip would “only cause confusion” at a time when the two countries are working to restore ties.

The spokesperson also accused the main opposition party of “engaging in fearmongering” and “going all the way to Japan to push domestic political objectives.”