It's the second court motion filed this week by Texas, which has sued the Environmental Protection Agency claiming the rules rely on flawed science and could lead to power outages.
Attorney General Greg Abbott initially asked the U.S. Court of Appeals in Washington to review regulations, announced in July, for coal-fired power plants. The state on Thursday filed another petition to block enforcement.
Gov. Rick Perry has insisted that new air pollution rules would also hurt the economy. The Republican has promised to minimize federal regulation if elected president.
The new rules would require states to reduce sulfur dioxide and nitrogen oxide emissions, which mostly come from coal-fired plants. Texas has 19 coal-fired power plants.
