PHNOM PENH (Reuters) - Elected officials of Cambodia’s banned opposition party have begun handing over their duties after a court ordered the party dissolved, the government said on Monday.

The Supreme Court outlawed the Cambodia National Rescue Party (CNRP) last week at the request of authoritarian Prime Minister Hun Sen’s government in a move that prompted the United States to cut election funding and threaten more punitive steps.

The party was banned after its leader, Kem Sokha, was arrested for alleged treason. The government says he sought to take power with American help. He rejects that allegation as politically motivated, to allow Hun Sen to extend his more than three decades in power in next year’s general election.

Among those told to give up their positions were councillors elected to communes in June, when the CNRP gained control of 40 percent of local councils, showing the electoral threat it posed to Hun Sen.

“The implementation has been going smoothly,” the Interior Ministry’s spokesman, Khieu Sopheak, told Reuters on Monday, adding that he did not know how long handover completion would take.

The ruling Cambodian People’s Party (CPP) will take over nearly all of the communes won by the opposition.

The CNRP’s 55 seats in the 123-member parliament will be shared among six minor parties, the National Election Committee (NEC) said. It had been unable to contact one of the parties entitled to a seat because its headquarters was shut, it added.

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Three NEC members submitted a letter of resignation from the electoral body in protest at their party’s dissolution, saying the redistribution of seats to other parties was “unconstitutional” and against “voters’ will”.

The court has also banned 118 CNRP party members from politics for five years.

Mu Sochua, a senior CNRP member who moved abroad shortly before the ban, said party officials met over the weekend outside Cambodia “to put together an action plan for the immediate future.”

“We reject the decision of the court,” she said, adding that Kem Sokha remained president and the party’s former leader, Sam Rainsy, had rejoined it.

Sam Rainsy had resigned in February, saying he feared the party would be banned if he did not, because of defamation convictions that he calls politically motivated and which pushed him to flee Cambodia in 2015.

Across Cambodia, police took down CNRP signs outside party offices and on the streets. The interior ministry spokesman said the CNRP had helped by taking down its Phnom Penh headquarters sign itself.

Rejecting the criticism from the United States over the dissolution of the opposition party and a crackdown on local rights groups and independent media, Hun Sen said on Sunday that Washington should cut off all aid for Cambodia.