PHNOM PENH (Reuters) - The United States has called on Cambodia to reverse steps that “backtracked on democracy” before a general election next year, a visiting U.S. official said on Wednesday.

U.S. Deputy Assistant Secretary of State for Southeast Asia, Patrick Murphy speaks during a news conference in Phnom Penh, Cambodia December 13, 2017. REUTERS/Samrang Pring

Relations between Cambodia and the United States have hit their lowest in years after the arrest of a rival of long-serving Prime Minister Hun Sen, Kem Sokha, and the dissolution of his opposition Cambodia National Rescue Party (CNRP).

Hun Sen accused Kem Sokha and his party of a U.S.-backed anti-government plot. The opposition leader and the United States denied that.

“We are advising that these steps that have taken place here that have backtracked on democracy could be reversed,” said Patrick Murphy, deputy assistant secretary of state for Southeast Asia, the most senior U.S. official to visit since the CNRP was dissolved.

Murphy told reporters in Phnom Penh that Cambodia still had time before the general election in July to “conduct an electoral process that is legitimate”.

Hun Sen looks set to extend his 32-year rule easily next year after eliminating the CNRP, which had made big gains in the last general election in 2013.

On Tuesday, the European Union followed a U.S. lead in suspending funding for the election.

Kem Sokha has been accused of plotting treason with unidentified Americans and the Cambodian Supreme Court dissolved his party last month at the government’s request. Kem Sokha said the charges were a political ploy.

Murphy said allegations of a U.S.-backed plot were a fabrication.

“We want a good relationship,” he said. “There is a little bit of friction, a little bit of noise in the official bilateral relationship but we remain optimistic.”

During his visit, Murphy met senior officials but no government ministers. He also met civil society groups.

Ouch Borith, secretary of state at the foreign ministry, who met Murphy on Tuesday, told reporters their talks had been about improving the relationship.

He defended his government’s actions.

“What we’ve done is in the legal framework to defend Cambodia’s independence, peace and stability. We didn’t do anything illegal,” he said.

Reaction to the dissolution of the CNRP has been largely muted in Cambodia.

Rights groups have decried what they say is an increasingly repressive atmosphere in the Southeast Asian nation, and have condemned the detention of several reporters and closure of some media outlets.

Hun Sen has shrugged off criticism from the West. China, Cambodia’s largest aid donor, has leant its support to Hun Sen saying it respects Cambodia’s right to defend its national security.