Harper and his Indian counterpart Manmohan Singh announced the completion of negotiations on the technical details that will permit a nuclear co-operation agreement to be ratified.
"This is a very important development for Canada," Harper said in New Delhi.
"Among developed nations, we are one of the few that has the entire spectrum of a civilian nuclear industry — all the way from uranium production to the construction of reactors."
Nuclear trade talks between India and Canada began in January 2009 but progressed slowly, blowing past Harper's November 2009 visit to the South Asia giant.
A nuclear co-operation agreement was signed in June 2010 but the implementation details remained to be worked out.
Given Canada's fraught nuclear history with India, the delays did not augur well.
India used a Canadian-supplied reactor to create the plutonium for its "Smiling Buddha" nuclear test blast in 1974.
The detonation harmed bilateral relations for two decades. It also sparked a nuclear sales moratorium and helped boost the global non-proliferation movement.
India has never signed the Treaty on the Non-Proliferation of Nuclear Weapons or the Comprehensive Test-Ban Treaty.
So the Canada-India deal is a watershed moment in the nuclear movement that goes beyond simply bilateral trade, say experts.
Even if Canadian uranium never makes it near a weapons facility, our exports will still free up India's domestic supply, said Cesar Jaramillo, a nuclear disarmament expert with Project Ploughshares.
"India requires uranium for both its civilian and military nuclear programs and, since it is generally in short supply domestically, the uranium imported for civilian needs may allow the country to allocate more of its domestic holdings for the military," Jaramillo said in an email.
More fundamentally, the deal signals that nuclear co-operation is acceptable with what remains effectively a rogue nuclear state.
"It defies logic that the Nuclear Suppliers Group would provide an exemption for nuclear trade with India, thereby 'rewarding' a country that is neither a member of the Nuclear Non-Proliferation Treaty nor a signatory of the Comprehensive Test-Ban Treaty — and continues to produce fissile material," Jaramillo wrote.
Warren Mabee, director of the Queen's University Institute for Energy and Environmental Policy in Kingston, Ont., said it is unclear what has changed from two years ago when concerns about weapons safeguards stalled the talks.
"Are we comfortable enough that the checks and balances are out there that will prevent those types of weapons from being generated or used?" Mabee asked. "Or have we just stopped worrying about that because now we're too focused on the economy?"
He's also concerned the deal appears to be framed around uranium sales, and not value-added technology such as SNC Lavalin's recent purchase of the Candu reactor division from AECL.
"From what I know this is a straight-up resource deal, that we're going to feed uranium into India and they'll be able to use it to generate power," said Mabee.
A Canadian government official in New Delhi, speaking on background, said only a last legal vetting and French and Hindi translation of the English "administrative arrangement" document stands in the way of the final signing and coming-into-force of the deal.
Details of the pact will remain secret, said the official.
But it appeared Tuesday that Canada may not have received all the oversight powers it initially wanted to trace Canadian uranium use once it arrives in India.
Instead, the deal ensures materials will go only to "facilities subject to safeguards applied by the International Atomic Energy Agency," or IAEA, according to a background document.
"We don't oversee, we'll be receiving those assurances from the IAEA," Aurele Gervais, a spokesman with the Canadian Nuclear Safety Commission, told The Canadian Press.
"The agreement that was successfully negotiated and will be signed in the near future will ensure that Canada receives the necessary assurances from India and from the International Atomic Energy Agency that the materials will be peacefully used."
India hasn't signed the non-proliferation or test-ban treaties but in February 2009 it agreed to begin reporting to the UN-based IAEA on its civilian nuclear plants.
"We wanted to get a better sense of the type of information that's being supplied (to the IAEA), and we're able to do that," said the Canadian official in New Delhi.
A joint committee that will meet annually will help smooth over implementation issues, research and development, nuclear science exchanges and other matters, said the official.
— With files from Bruce Cheadle in Ottawa
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