WASHINGTON • The United States Supreme Court was divided evenly over President Barack Obama's plan to shield as many as 4 million unauthorised immigrants from deportation - a deadlock that effectively kills the initiative for the rest of his presidency.

The 4-4 split leaves intact an appeals court ruling that said Mr Obama overstepped his authority, along with a trial judge's order preventing the programme from taking effect. The court action does not mean those immigrants will be deported, but it blocks a programme that would have let them seek work permits.

In a press conference yesterday, Mr Obama said the decision would be "heartbreaking" for millions of immigrants in the US.

The deadlock may stoke what already is a fiery debate in the presidential campaign over the 11 million people who are in the US illegally.

Presumptive Republican presidential nominee Donald Trump has said he would deport them, temporarily halt immigration for Muslims, and turn back Syrian refugees. He also wants to build a wall along the Mexican border to prevent illegal immigration in the future.

Mrs Clinton called the court deadlock "unacceptable" and said in a statement that she believed Mr Obama "acted well within his constitutional and legal authority".

Mr Obama acted after Congress hit a stalemate in efforts to pass a comprehensive overhaul of immigration laws. Under the programme, people whose children are either US citizens or legal permanent residents, and who meet other requirements, could have been given relief from deportation for three years.

Those individuals, who are primarily from Mexico and Central America, would not have been given an easier path to citizenship.

House Speaker Paul Ryan, a Wisconsin Republican, said the ruling "makes the President's executive action on immigration null and void". He said: "The Constitution is clear. The president is not permitted to write laws - only Congress is."

BLOOMBERG, REUTERS