"I would not do business with North Korea," he was quoted by the agency as saying.

Taiwan's justice ministry last week announced a ban on all financial dealings with Chen and froze his companies' bank accounts due to the ongoing investigation into his activities.

Chen is being probed over links to a Hong Kong-registered ship that Seoul has said it detained in November.

The ship, known as the Lighthouse Winmore, is suspected of transferring oil products to a North Korean vessel and breaching UN sanctions against the nuclear-armed regime.

Chen is under investigation for making a false declaration that a ship he chartered was bound for Hong Kong when it actually sailed to international waters to sell oil, according to prosecutors.

He has told prosecutors that he did not know the oil products were bound for a North Korean vessel, sources told AFP. 

Local media said the ship he chartered was the Lighthouse Winmore and that Chen sold oil products through "a Chinese middleman."

The Lighthouse Winmore was impounded in November by South Korean authorities after it allegedly transferred 600 tonnes of oil to a North Korean vessel, according to Seoul.

It was chartered by the Billions Bunker Group, which is incorporated in the Marshall Islands and cannot be traced directly to Chen.

But Taiwanese authorities found him to be the sole shareholder of another company with a similar name, Bunker's Taiwan Group, incorporated in the British Virgin Islands. 

Taiwan has slapped sanctions on both firms.

Two other entities backed by Chen were also sanctioned by Taiwan under terrorism financing prevention laws.

Chen is currently on bail and has not yet been formally charged.

The US had previously asked the United Nations Security Council to blacklist 10 ships -- including the Lighthouse Winmore -- for violating sanctions against the North. 

Taiwan announced in September it was banning all trade activities with North Korea. (AFP)