South Korea on Friday denied a report that it would sell artillery shells for use by Ukrainian forces, claiming that the munitions -- if the ongoing deal negotiation is finalized -- will be for US forces only.

The United States was nearing an agreement to purchase 100,000 rounds of 155 mm artillery from Seoul which would be delivered to Ukraine, The Wall Street Journal reported on Thursday, citing "US officials familiar with the deal."

Washington is Seoul's key security ally and stations some 27,000 US troops in the South.

South Korea claimed on Friday that while the arms deal with the US is ongoing, the shells are not meant to be delivered to Ukraine.

"In order to make up for the shortage of 155mm ammunition inventories in the US, negotiations are ongoing between the US and a (South Korean) company to export ammunition," Seoul's Defense Ministry said in a statement.

"This is being done under the premise that the United States will be the final user" of the shells, it insisted.

The Ministry added that South Korea's "policy of not providing lethal weapons to Ukraine remains unchanged."

It is noteworthy that Seoul is an increasingly important arms exporter, recently inking a deal to send its domestically-produced tanks and howitzers to Poland.

The discussions between the US and South Korea come after Washington accused North Korea of shipping artillery shells to Russia to use in Ukraine.

Pyongyang has dismissed the claim, calling it "groundless".

The Pentagon announced Thursday that the United States will provide air defense systems and surface-to-air missiles to Ukraine as part of a new $400 million security aid package.

The package includes missiles for HAWK air defense systems that Spain has agreed to provide, artillery and mortar rounds, ammunition for HIMARS precision rocket launchers, and more than 20 million rounds of small arms ammunition.

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