He is expected to announce the start of free trade talks with one nation and exploratory negotiations with the other before heading to a nuclear security summit in Korea.
Spokesman Andrew MacDougall says there is much eagerness to expand economic ties beyond the already deepening relationships with China and India.
He says at security summit 53 world leaders are expected to focus not only on questions of weapons proliferation, but on the need to better oversee the peaceful use of atomic energy.
The subject was underscored last year following the disaster in Japan when the tsunami wrecked the Fukushima power plant.
Harper will visit the northern Sendai region in an expression of solidarity with the people of Japan _ It comes just after the first anniversary of the disaster on March 11.
With regards to the summit, MacDougall highlighted the range of ongoing international programs meant to round up loose nuclear material and other items that can be used in weapons of mass destruction, something Canadian taxpayers have quietly contributed $820 million towards since 2002.
Although, when it comes to nuclear issues, MacDougall conceded that most of the attention is focused on rogue nations like Iran and North Korea — a thorny topic that's bound to come up. "It's unavoidable the subject will be raised, but I think the summit will work at stopping proliferation and securing (nuclear materials)," he said.
The trip comes within a month of Harper's trip to China, where the primary focus was on improving relations and opening up Canadian oil and gas to the energy-hungry country.
While in Thailand, the prime minister is expected to receive an update on that country's efforts to put an end to human smuggling. Many illegal migrant networks have used the South Asian country as a transit point.
Harper and the Thai prime minister are expected to announce the launch of a study to see whether a free-trade arrangement between the two countries is feasible.
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