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By Hyonhee Shin
SEOUL, Aug 15 (Reuters) - South Korean President Moon Jae-in said on Thursday that Japan should look back upon its imperialist past but Seoul will "gladly join hands" if Tokyo chooses dialogue, in a carefully choreographed message amid an escalating history and trade row.
In his Liberation Day address marking Korea's independence from Japan's 1910-45 colonial rule, Moon refrained from deriding Japan but laid out ambitious goals for inter-Korean relations, including an unprecedented call for unification by 2045.
Moon warned the global free trade order may suffer if a country "weaponises" a sector where it has an upper edge, referring to curbs Japan has imposed on exports of some high-tech materials to South Korea.
Seoul calls the move as retaliation over a feud about wartime forced labour, while Tokyo cited unspecified security reasons.
The dispute, triggered after a South Korean court ordered Japanese firms last year to compensate some of their former labourers, has brought their ties to their lowest ebb in more than half a century.
Japan sees the issue was settled by a 1965 treaty normalising bilateral ties.
But Moon said the two neighbours can overcome the past and move toward the future if Japan "contemplates a past that brought misfortune to its neighbouring countries".
"Better late than never: if Japan chooses the path of dialogue and cooperation, we will gladly join hands," Moon said.
Moon also painted a brighter outlook for the two Koreas, vowing efforts for a successful joint hosting of the 2032 Olympics and an eventual unification by 2045.
Such goals have long been considered distant, but come at a particularly sensitive time amid the North's ongoing series of missile tests, stalled nuclear talks with the United States and virtually severed inter-Korean communications.
"In spite of a series of worrying actions taken by North Korea recently, the momentum for dialogue remains unshaken," Moon said.
"I pledge to solidify the foundation so that we can ... stand tall in the world as one Korea by achieving peace and unification by 2045, which will mark the 100th anniversary of liberation."
(Reporting by Hyonhee Shin; Editing by Michael Perry)