By Lawrence Hurley

WASHINGTON (Reuters) - The U.S. Supreme Court on Tuesday delivered a major blow to President Barack Obama by blocking federal regulations to curb carbon dioxide emissions from power plants, the centerpiece of his administration's strategy to combat climate change.

On a 5-4 vote, the court granted a request made by 27 states and various companies and business groups to block the administration's Clean Power Plan. The move means the regulations will not be in effect while litigation continues over whether their legality.

The brief order from the justices said that the regulations would be on hold until the legal challenge is completed. The court's five conservatives all voted to block the rule. The order noted that the four liberals would have denied the application.

A U.S. appeals court in Washington had turned away a similar request on Jan. 21.

The states, led by coal producer West Virginia and oil producer Texas, and several major business groups in October launched the legal challenges seeking to block the Obama administration's plan.

More than a dozen other states and the National League of Cities, which represents more than 19,000 U.S. cities, filed court papers backing the Environmental Protection Agency's rule.

The appeals court still must hear oral arguments on June 2 and decide whether the regulations are lawful.

(Reporting by Lawrence Hurley; Editing by Will Dunham)