Six U.S. senators are urging the U.S. Environmental Protection Agency (EPA) to stop its pending proposal to create stricter pollution standards for gasoline and vehicles because of an underlying concern that enforcing stricter standards will escalate the price of gasoline.

In a letter to Lisa Jackson, U.S. EPA administrator, the group of senators asked the agency to “reconsider the timing” of the pending proposal, titled the “Tier III” fuel and vehicle rules. The senators mirror increasing criticisms from the oil industry and others that the rule, expected to tighten the existing cap on sulphur in gasoline of 30 parts per million (ppm) down to 10 ppm, will increase gas prices. The proposed regulations have yet to be made formal, even though sources say that the agency’s Office of Transportation and Air Quality has completed its work on the rulemaking.

“With gas prices already high, and with so many Americans already struggling to make ends meet, we urge you to recognize that now is not the time for new regulations that will raise the price of fuel even further,” the senators wrote to Jackson.

In their letter, the senators cited an oil-industry-backed study, which predicts that fuel costs would increase 12 to 25 cents if the Tier III rule was released as proposed. The senators also argue that the proposal could cause some refineries to shut down due to the costs to implement the rule, leading to job losses.

In another letter to the EPA administrator, seven public health groups, including the American Heart Association and the American Lung Association, are urging Jackson to move forward with the Tier III rules as quickly as possible.

Links to the two letters sent to the EPA administrator will soon be available on the Automotive Service Association’s legislative website, www.TakingTheHill.com.