Kim Yo-jong, the sister of North Korean leader Kim Jong-un / Yonhap

The sister of North Korean leader Kim Jong-un said Friday that President Moon Jae-in's proposal to declare a formal end to the Korean War is an "admirable idea" and Pyongyang is willing to discuss improving inter-Korean relations if Seoul ceases to be hostile toward it.

Kim Yo-jong stressed, however, that the right conditions should be created first before an end-of-war declaration is adopted, such as the removal of what she called "inveterate hostile policy and unequal double standards" toward the North.

Her statement came just hours after a vice foreign minister of the North dismissed Moon's end-of-war declaration proposal as "something premature," saying such a declaration would end up as nothing more than a scrap of paper as long as the U.S. hostile policy remains unchanged.

While the earlier statement from Vice Foreign Minister Ri Thae-song appeared to be geared toward the United States, the statement from the North Korean leader's sister was seen as targeted more toward South Korea.

"The declaration of the termination of the war is an interesting and an admirable idea. ... But it is necessary to look into whether it is the right time now and whether there are conditions ripe for discussing this issue," Kim said in a statement carried by the official Korean Central News Agency.

"Now double-dealing standards, prejudice and hostile policies toward the DPRK and speeches and acts antagonizing us persist. Under such situation it does not make any sense to declare the end of the war with all the things, which may become a seed of a war between parties that had been at odds for more than half a century, left intact," she added.

DPRK stands for the North's official name, Democratic People's Republic of Korea.