CALGARY -- A senior TransCanada Corp. executive says the resistance to the approval of the proposed Keystone XL oilsands pipeline has made the company more cautious about future cross-border endeavours.

Alex Pourbaix, president of energy and oil pipelines at the Calgary-based pipeline and utility company (TSX:TRP), said the long delays getting Keystone approved in the U.S. has been an education.

"When you're involved in one of these cross-border projects you require a presidential permit. At any time in the process, especially one that goes four or five years, you get caught up in the election cycle," Pourbaix said Thursday.

"I think it's not a surprise to anybody that this project, to some degree, has been caught up in election politics and it's added to the time. We just have to be careful in thinking about that as we go forward with these kind of projects."

The future of Keystone is still fuelling battles in Washington, D.C.

The $7 billion Keystone XL pipeline would bring 700,000 barrels of oilsands crude a day from Alberta through six states and to Gulf Coast refineries.

Republicans in the House of Representatives made yet another attempt this week to take the decision out of U.S. President Barack Obama's hands.

Legislators voted 241-175 in favour of the Northern Route Approval Act, which would give Congress the power to green-light the pipeline and nix the need for a presidential permit. The bill, however, faces a far less certain future in the Democrat-controlled U.S. Senate.

The White House has threatened to veto the bill, saying it "seeks to circumvent long-standing and proven processes for determining whether cross-border pipelines are in the national interest."

Pourbaix, who speaking to business leaders about getting Alberta's oil and natural gas to market, said he expected Keystone to be a challenge, but not to this degree.

"When we went into Keystone XL I think it would be fair to say we knew we were going to have challenges but I don't think anybody could have foreseen the kind of opposition," he said.

"In the first two phases of Keystone, we received our presidential permit in 21 months. We are now well into our fifth year of permitting Keystone."

Pourbaix said TransCanada will work harder in the future to ensure that people and governments along routes are onside before moving forward. He said the opposition to pipelines such as Keystone XL isn't about safety.

"This is about a fight over trying to stop the development of the oilsands by choking off the pipeline projects and I think we all have to remember that," he said. "As we go forward on new projects we're obviously going to take that into account."