Liberal Leader Stéphane Dion in Ottawa on June 19 when he unveiled the party's new green plan. (CBC)

An environmental consulting and supply company in Toronto is firing off a legal "cease and desist" order to stop the Liberal party from using the firm's trademark name — Green Shift — for its new carbon-tax plan.

In what could become an embarrassing confrontation for Liberal Leader Stéphane Dion, the owner of Green Shift says she is taking the legal step after earlier attempts failed to get the Liberals to drop the name from their environmental plan.

Environmental consultant Jennifer Wright, who has owned Green Shift since 1999 and registered the company name in 2001, said Monday she and a handful of other dedicated environmentalists who work with the firm can't afford to have its identity associated with any political party.

But efforts that began last week, when Dion unveiled the Liberal party's so-called Green Shift, have yielded no results. Wright said legal action may be the only recourse.

"We're just trying to ask them politely to do the right thing," she said in an interview. "We have asked them to stop using the name and we've asked them for a full public apology."

A Liberal spokesman confirmed the party knew of the Green Shift company before Dion's announcement, saying someone contacted Green Shift before Dion announced the scheme last week.

"A courtesy call was made last Monday in advance of (the) launch to let them know they might get increased traffic," said Mark Dunn, Dion's communications director.

Wright, however, said the call came on Wednesday and it was unclear exactly what the Liberal representative who called intended by the conversation.

'A David and Goliath problem'

Wright and her associates have spent the past few years initially consulting with private firms who want to change their consumption and purchasing toward environmentally sustainable or green choices.

The firm, in partnership with a United States association in support of the blind, began distributing what she called the first biodegradable cup in the world, which has the name Green Shift under its lip.

"For us to take this further [against the Liberals], it's a David and Goliath problem," Wright said. "We're fine on our own, without any political affiliation. We've done everything to build our name on trust and integrity."

She added the company has worked with government departments of all stripes across the country, including consulting with the Ontario NDP for its election campaign last year, and cannot afford being associated with any one party.

A Liberal spokesman discounted the company's protests that the Liberals mimicked Green Shift's web domain name, by adding the article "the" before Greenshift.ca.

"We rightly own the domain name," said Dunn. "We are not a commercial threat to the company. The content of our site is about policy, not products."

Meanwhile, Jason Kenney, a Conservative cabinet minister, said the incident showed "how competent Dion is" to pick up a name that belongs to a private company to make it the centrepiece of his election campaign.

"It looks like he may well be forced to drop the green shift in which case I guess he'll have to have truth in advertising and call it 'the green tax on everything' and Canadians will end up paying through the nose if he succeeds in imposing it."