Canadian Prime Minister Stephen Harper said Sunday that he was looking at exporting more oil to China after the United States delayed a decision on a controversial pipeline.

President Barack Obama's administration last week put off a decision on Keystone XL project after a major protest campaign by environmentalists, who say the pipeline would be prone to accidents and worsen climate change.

The conservative Canadian leader, taking part in a summit in Hawaii hosted by Obama said the pipeline decision had produced "extremely negative reactions" and that he discussed oil exports with Chinese President Hu Jintao.

"This does underscore the necessity of Canada making sure that we are able to access Asian markets for our energy products," Harper told reporters. "I indicated that yesterday (Saturday) to President Hu of China."

The Harper government has pressed Obama to approve the 1,700-mile (2,700-kilometer) pipeline extension, which would stretch through Montana, South Dakota, Nebraska, Kansas and Oklahoma before ending up in Texas.

Canada, the pipeline's lead company TransCanada, and Obama's Republican opponents say the $7 billion project would provide the United States with a stable source of energy from an ally and create thousands of jobs.

"I remain optimistic that the project will eventually go ahead because it makes eminent sense," Harper said.

"This project is obviously what's in the best interest not just of the Canadian economy but also of the American economy," he said.

But environmentalists say an accident would be disastrous for aquifers in the US Great Plains and point to spills on an existing Keystone pipeline. The oil comes from tar sands, meaning it produces high levels of carbon emissions blamed for global warming.

The Obama administration, in ordering further study, cited particular concern about the pipeline's planned route through the Sand Hills area of Nebraska, which has a sensitive ecosystem and shallow groundwater.

The State Department delayed a final decision until 2013, after next year's presidential election.