A BP PLC (BP, BP.LN) and ConocoPhillips (COP) joint venture said Tuesday that it is scrapping a $35 billion Alaska natural gas pipeline project because of weak customer demand and poor project economics.

Denali , the joint venture, had proposed building a 1,700-mile pipeline from the Alaska 's oil- and gas-rich North Slope to Alberta , Canada . The pipeline would have shipped about 4.5 billion cubic feet a day of gas.

A rival project proposed by TransCanada Corp. (TRP, TRP.T) and Exxon Mobil Corp. (XOM) is still on track, TransCanada said Tuesday. That project, estimated to cost up to $41 billion, has a license and financial backing from the
Alaska government.

Denali 's project, which didn't have state backing, appears to have been more vulnerable to recent low natural gas prices, while TransCanada's project has enjoyed strong support from two Alaska administrations.

Denali said it was unable to secure financial commitments from gas producers on Alaska 's North Slope despite 18 months of negotiations. Major producers in the area include BP, ConocoPhillips and Exxon.

Denali also blamed low gas prices and strong domestic supplies of natural gas produced from shale rock in Texas and other parts of the U.S. for the project's cancellation.

Spokesman Scott Jepsen said
Denali had unsuccessfully sought more than $100 billion in financial commitments from Alaska gas producers to build the project.

"We've been trying to get some agreements...that have teeth in it so we could continue [developing] the pipeline," Jepsen said. "We haven't been able to get the level of support we require...the impact that shale gas has had on North American markets," particularly "near-term [low] natural gas prices certainly haven't helped the project."

Jepsen declined to provide details of
Denali 's negotiations or to name any of the oil and gas producers, citing confidentiality agreements. He also wouldn't say how many people are employed by Denali , although said the joint venture was made up mostly of employees on loan from BP and ConocoPhillips, who would return to jobs at their respective companies. The company said it spent $165 million on the effort.

Rival Pipeline Progresses

Tony Palmer, TransCanada's vice president of Alaska development said, "We continue to be confident that we can advance with the project."

TransCanada and Exxon Mobil Corp. have proposed building a $32 billion-$41 billion 1,700-mile pipeline from
Prudhoe Bay on Alaska 's North Slope to Alberta , Canada , which would connect with TransCanada's existing pipeline system that carries gas into the U.S. The pipeline would ship up to 4.5 billion cubic feet a day of gas and could be expanded to carry 5.9 billion cubic feet a day.

Low gas prices won't affect TransCanada's pipeline project, Palmer said. Since it is scheduled to go online around a decade from now, the only gas prices that matter are those in effect at that time, he said.

"The timeframe for this project is not today or tomorrow, it's 2020 and beyond," Palmer said.

Key negotiations remain, including talks between TransCanada and oil and gas producers in
Alaska over terms of a pipeline shipping agreement, and talks between producers and the state of Alaska over production taxes and incentives, he added.

TransCanada has a license and financial backing from the state of
Alaska , obtained during former Gov. Sarah Palin's administration. The license includes a 10-year guarantee that locks in tax rates for producers. However, producers have said the 10-year term is too short, in part because it doesn't match up with a pipeline commitment, which would likely be 20 years or longer.

Alaska Gov. Sean Parnell, a strong supporter of the pipeline project, said Tuesday that he hopes TransCanada and Exxon's project will proceed, with the participation of BP and ConocoPhillips.

"While we dislike seeing the demise of any gas pipeline project before a gasline is under way, the silver lining here is that
Denali 's announcement frees ConocoPhillips and BP to independently become partners in another Alaska gasline project," Parnell said. He added "alignment" among gas producers, the pipeline developers and state and federal agencies "will be necessary to advance a project of this magnitude."