Political analysts at a conservative Washington-based think tank have called for the US to reconsider its relationship with Cambodia in the wake of the disputed July election.

Promoting True Democratic Transition in Cambodia, released by the Heritage Foundation last week, urges the US to focus on promoting democracy in Cambodia after a vote the opposition and rights groups say was marred by fraud.

“The 2013 elections were and are a watershed moment, an opportunity for the US to take stock of what it has accomplished in Cambodia and press for long-overdue political reforms,” the report says.

For eight months, the Cambodia National Rescue Party has organised mass demonstrations and refused to take its seats in the National Assembly, claiming it won more seats than the Cambodian People’s Party, and that many votes weren’t properly accounted for.

According to the report, Cambodia is crucial to US interests.

“It is critical . . . that Cambodia mature into a self-sustaining, democratic nation . . . prepared to combat modern-day challenges to governance and peace and security in the Pacific.”

The report calls on the US to push for a credible investigation into the July election and to be “more publicly critical” of Prime Minister Hun Sen.

If Cambodia fails to meet the US’s existing demands for reform – the House of Representatives has suspended some funding until the election deadlock is resolved – the report advises the additional “termination of small amounts of security assistance”.

“The US should also oppose the resumption of World Bank programs if the certification requirement is not met,” it says. The World Bank froze new lending to Cambodia in 2011.

Other suggestions include a review of the impact of economic assistance and democracy programs and the establishment of a “contact group” to press for democratic reforms.

But Ou Virak, chairman of the Cambodian Center for Human Rights, said reforms could prove a “difficult balancing act” for the US. “Reform is something that ultimately must be resolved domestically.”