PHNOM PENH (Reuters) - The U.S. ambassador to Cambodia rejected government accusations of interference as  inaccurate, misleading and baseless  on Tuesday, and called for the immediate release of opposition leader Kem Sokha. The government of Prime Minister Hun Sen has charged Kem Sokha with treason, accusing him of conspiring to take power with the help of the United States, which has become an increasing target of Hun Sen s rhetoric.  On dozens of occasions over the past year, the United States has been subject to intentionally inaccurate, misleading and baseless accusations,  Ambassador William Heidt said in a statement.  All of the accusations you have heard in recent weeks about the United States - every one of them - are false,  he said. Heidt called for the immediate release of Kem Sokha. 