May 23 (Reuters) - Nineteen Republican attorneys general

have filed a rare complaint directly with the U.S. Supreme Court

asking it to block several Democratic-led states from pursuing

climate change-related litigation against major oil and gas

companies in state courts.

The challenge, which legal experts say is unlikely to be

successful because it raises arguments that are similar to ones

the court has already refused to consider, was filed on

Wednesday by states including Alabama, Florida and West Virginia

against five Democratic-led states.

The complaint alleges that California, New Jersey,

Connecticut, Minnesota and Rhode Island, by suing major energy

companies in state court seeking damages for the harms of

climate change, are essentially trying to regulate global

emissions and the U.S. energy system. The lawsuit asks the high

court to enjoin the defendant states from suing the companies

over emissions or the sale and promotion of fossil fuel products

in the plaintiff states.

Those regulatory powers are reserved for the federal

government under federal law, the Republican-led states said.

"These states are welcome to enforce their preferred

policies within their jurisdiction, but they do not have

authority to dictate our national energy policy," said Alabama

Attorney General Steve Marshall in a statement.

The five states are among dozens of states and

municipalities that have filed similar lawsuits against major

fossil fuel companies such as Exxon, ConocoPhillips ( COP )

, Shell and BP, alleging the companies

knew for decades that burning fossil fuels would lead to climate

change but worked to conceal that fact from the public. They

claim the companies created a public nuisance or violated state

laws in doing so.

The energy companies did not immediately respond to requests

for comment on Thursday. They have argued the lawsuits seek to

regulate interstate emissions or commerce, which are powers

reserved for the federal government.

"This is pure partisan political theater," Connecticut

Attorney General William Tong, a Democrat, said in a statement.

"Our case is about truth in advertising, and not emissions

controls."

The Supreme Court refused last year to hear bids by oil

companies to move several of the lawsuits to federal court,

after numerous U.S. appeals courts said the claims are not

preempted by federal law.

Fossil fuel companies made similar arguments before the high

court in February in an effort to scrap a decision allowing a

lawsuit filed by Honolulu, Hawaii, to go to trial. The request

is pending.

Legal experts said the Supreme Court is unlikely to take the

case filed Wednesday, noting the court has discretion to do so

and has already seen the arguments.

"The arguments are almost entirely variations on those that

were raised by the fossil fuel industry in their unsuccessful

attempts to argue that these suits belong in federal court,"

said Doug Kysar, a professor at Yale Law School.

The case is State of Alabama et al. v. State of California

et al., in the U.S. Supreme Court, case number not immediately

available.

For the challengers: Their respective attorneys general

offices

For the defendants: Their respective attorneys general

offices