OTTAWA, June 20 (Reuters) -

The Pathways Alliance, a group of Canada's biggest oil sands

producers, has removed all content about environmental goals

from its website and social media pages, citing "significant

uncertainty" over the federal government's proposed

anti-greenwashing legislation.

Bill C-59, which only needs royal assent to become law after

Canada's parliament gave approval on Wednesday, would force

companies to show proof of their environmental claims.

Pathways is proposing a C$16.5 billion ($12.04

billion)carbon capture and storage project to cut carbon

emissions from the oil sands, but has faced criticism from

environmentalists for slow progress and seeking more government

financial support.

On Thursday, the content on Pathways' website had been

replaced with a post about its concerns with omnibus Bill C-59,

which will implement the Liberal government's mid-year budget

proposals and change Canada's Competition Act.

"Imminent amendments to the Competition Act will create

significant uncertainty for Canadian companies that want to

communicate publicly about the work they are doing to improve

their environmental performance," the website said.

On Wednesday, the website had said "Canada's oil sands

are on a path to reach net-zero emissions from operations,"

according to an archived copy.

The alliance, which includes oil sands producers Suncor

Energy ( SU ), Imperial Oil ( IMO ), and Cenovus, did

not immediately respond to a request for further comment.

The post on Pathways' website also said specific guidance

from Canada's Competition Bureau may help direct its

communications approach in future, and added that the group

"remains committed to the work we are doing."

Canada is the world's fourth-largest oil producer and

the oil and gas sector is the country's highest-polluting

industry, accounting for more than a quarter of all emissions.

Climate advocacy group Environmental Defence said

Pathways' decision to take down content shows "they don't have

evidence to support the story they're selling."

The Canadian Association of Petroleum Producers (CAPP) said

it was extremely disappointed with the amendments.

"The effect of this legislation is to silence the energy

industry and those that support it in an effort to clear the

field of debate and to promote the voices of those most opposed

to Canada's energy industry," CAPP President Lisa Baiton said in

a statement.

Bill C-59 was amended earlier this year to add

anti-greenwashing rules and has already cleared the lower House

of Commons and awaits passage by the unelected upper chamber of

the parliament.

($1 = 1.3699 Canadian dollars)