A Japanese journalist on trial in Seoul for allegedly defaming South Korean President Park Geun-Hye met the Japanese premier Wednesday, a day after his travel ban was eased.

Tatsuya Kato, the former Seoul bureau chief of Japan's conservative Sankei Shimbun newspaper, arrived in Tokyo Tuesday evening after Seoul lifted an eight-month-old order barring him from leaving South Korea.

After a 20-minute meeting with Prime Minister Shinzo Abe, Kato told reporters he was "thankful for the Japanese government's efforts" and "for encouraging him".

Kato said Abe had asked him "to take care of himself" since he must return to court later to face the culmination of a trial over a column he wrote about Park's whereabouts on the day the Sewol ferry sank a year ago with the loss of more than 300 lives.

Japan's top government spokesman Yoshihide Suga told a press conference Wednesday that Tokyo "will continue to call on South Korea to take appropriate steps".

Kato's column, published in the online edition of the Sankei in August, suggested the unmarried president had disappeared for an ill-timed tryst with her former aide on the day of the ferry tragedy.

Kato was banned from leaving South Korea shortly after the article was published. He is due to appear in court again on April 20.

Kato has denied criminal libel, a crime punishable by up to seven years in prison.

He has insisted his objective had been to report the public perception of Park in the wake of the Sewol disaster.

South Korean defamation law focuses on whether what was said or written was in the public interest -- rather than whether it was true.

Media freedom group Reporters Without Borders has defended the Sankei journalist, while Japan has formally voiced grave concern at Kato's prosecution and questioned Seoul's commitment to press freedom.

The Sankei, a robust centre-right daily that has campaigned to reverse a Japanese apology for forcing Korean women into wartime brothels, has suggested it is being singled out by Korean authorities.