LG Chem, an EV battery supplier for Tesla and General Motors, filed its trade complaints against SK Innovation last year in the United States over allegations of trade secret theft, seeking to block SK from producing battery cells in the United States and importing the components necessary to make the cells. SK denied wrongdoing.

The ITC decision was initially planned for early October.

An adverse ruling by the ITC could lead to the import ban of SK Innovation's batteries and necessary components, potentially causing setbacks for Volkswagen and Ford Motor as they move to build new electric vehicles.

"It is clear that this delay has resulted in a longer litigation process," SK Innovation said in a statement, adding it "hopes that the two firms could make a wise decision to wash off uncertainties caused by prolonged litigation by ending this dispute promptly and to focus on businesses."

Bert C. Reiser, counsel to LG Chem, said the company remains "extremely confident that the commission will hold SK Innovation responsible for their theft and issue appropriate remedies to make LG Chem whole."

Shares of LG Chem dropped as much as 2.9%, while SK Innovation saw its shares rise as much as 3.0% versus a 0.2% drop in the broader market KOSPI in morning trade.

Analyst said the ITC's decision to delay its final determination is adding uncertainties for LG Chem, while giving SK Innovation more time to review the lawsuit after the ITC initially ruled in favour of LG Chem in February.

Roh Woo-ho, an analyst at Mertiz Securities, said the delay could indicate the ITC "is facing difficulties making the final determination on the case, considering the impact it will bring to industrial issues in the United States including job issues."

He also noted the delay pushes a decision past the Nov. 3 U.S. election. Opinion polls show a tight race between Republican President Donald Trump and Democratic candidate Joe Biden in Georgia, with an Atlanta Journal-Constitution poll released on Monday showing Biden favored among likely voters 47% to 46%.

(Reporting by David Shepardson in Washington and Heekyong Yang in Seoul; Editing by Grant McCool and Richard Pullin)

By David Shepardson and Heekyong Yang