B.C.'s carbon tax, which took effect July 1, adds almost 2.5 cents to a litre of fuel. (CBC)

The British Columbia government should freeze further carbon tax increases while it gauges their effectiveness, a prominent business group told an all-party budget committee Monday.

The Vancouver Board of Trade kicked off a series of province-wide budget consultations by the select standing committee on finance and government services with the appeal for a freeze on the controversial carbon tax.

"We recommend the government postpone implementation of further carbon tax increases pending evaluation of any changes in [consumer] behaviour and usage of carbon-based products to determine if some permanent shifts and travel patterns have occurred," said board member Bernard Magnan.

He said the province is "offsetting the tax by returning these revenues to businesses and individuals in the form of lower taxes," but he urged the government to monitor the tax-neutral plan to ensure it accomplishes its climate improvement objectives.

"The government must also measure the impact of these measures, making sure the carbon emissions reductions are achieved," he said.

The board was one of several groups presenting submissions to the 10-person standing committee, made up of four NDP members and six Liberals.

The submission prompted New Democrat committee member John Horgan to ask Magnan to elaborate.

"I think I just heard some news there," Horgan said. "If I understand you correctly, the board of trade is recommending that the carbon tax stay at $10 per tonne and not go up in 2009?"

Magnan said the board was "suggesting that any further increases be postponed until we examine the impact of the first [part] of the carbon tax and see if that has achieved some of the goals that were meant to be."

The carbon tax kicked in July 1 and adds almost 2.5 cents to a litre of fuel.

The tax, introduced in last February's budget, will be phased in over five years to give consumers and businesses time to adjust and begin to understand there is a cost associated with generating harmful greenhouse gases.

The carbon tax starts at a rate based on $10 per tonne of carbon emissions and rises $5 a year to $30 per tonne by 2012. The tax works out to an extra 2.4 cents a litre on gasoline, rising to 7.24 cents per litre by 2012.