China’s President Hu Jintao just concluded on a victorious trip Havana on Tuesday – expanding a trade pact that could divert commodities from open spot markets.

It’s no secret that China has largely been responsible for the commodity run-up of the past few years. Now the question remains if the latest deal with Cuba could give China a new lost-cost provider of commodities. If so, it could be a bit of bad news for investors looking for a China-driven commodities run-up.

On Tuesday, Chinese president arrived in Cuba as part of a Latin American tour to strengthen ties with the resource-rich region. And his timing was impeccable.

Just weeks after Cuba’s farm sector and overall economy were rocked by three hurricanes which inflicted more than $10 billion, China parachuted in with almost a dozen trade agreements, according to Cuba’s state-run news agency.

In exchange for wider access to Cuba’s natural resources, China will rehabilitate the country’s decrepit infrastructure.

High on China’s Cuban shopping list were nickel, sugar and other agricultural products. By going direct, China is able to bypass the public markets whose fortunes have been riding on its voracious appetite for commodities.

As it now stands, China is Cuba’s second-largest trading partner, with both sides generating $2.7 billion annually – only about 3% of China’s overall trade with Latin America last year. This ranks China as second, after Venezuela, whose trade with Cuba was pegged at $7 billion.

While it may be easy to pooh-pooh Cuba’s contribution as minor, the fact is the Castro brothers are sitting on a bounty of nickel, tobacco, sugar, offshore oil, iron ore and copper. And most of it could conceivably head straight into China, deflecting potential gains from the open markets.

Earlier this month, when China said it would spend an estimated $586 billion over the next two years on a massive national infrastructure build-out, the commodity bulls roared out of the gates – expecting this new initiative to give prices a boost.

At the time, we wrote that the impact of the China plan would be minimal on commodity prices – and now with the Cuban deal we’re sticking to our guns.

But if anyone really wants to know what China’s plans for Cuba really are, just look to Macau.