Whether to deploy an advanced U.S. missile defense system in South Korea should top the agenda when President Park Geun-hye meets with U.S. President Barack Obama in Washington next month, the ruling party floor leader said Tuesday.
  

Park is scheduled to fly to Washington in mid-June for her fourth one-on-one summit with Obama, which will likely focus on their alliance, North Korea's nuclear threats, and other issues of mutual and global concern.
  

The call by Rep. Yoo Seong-min of the Saenuri Party came as the U.S. apparently is pushing to deploy the Terminal High Altitude Area Defense system in South Korea amid growing North Korean nuclear and missile threats.
 

U.S. Secretary of State John Kerry discussed the growing security threats from North Korea in a speech to U.S. military personnel at the Yongsan Base in Seoul on Monday, saying, "This is why we need to deploy ships, forces ... and we are talking about THAAD."
  

Mindful of the heavy costs and the Chinese resistance from a possible deployment, Seoul has been reserved about discussing the issue.
  

But now that North Korea's surface missile has become a real military threat along with its push for the development of submarine-launched ballistic missiles, South Korea and the U.S. should build up an optimal missile defense plan in the shortest time possible, the ruling party floor leader said.
  

"The South Korea-U.S. alliance can react to such North Korean threats effectively only after they act more closely than ever to construct the best-fitting missile defense in the shortest time possible," Yoo said in a party meeting. "These points should top the agenda in the forthcoming South Korea-U.S. summit."
  

Since last year, the U.S. state and defense departments, as well as key U.S. military officials, have publicly mentioned missile defense systems, including THAAD, but the South Korean government has only insisted that no discussion or decisions have been made between the allies on the issue, Yoo said.
  

"Seoul's repeated rejection of such a plan is not normal for the South Korea-U.S. alliance," he said. (Yonhap)