like many countries in the last 6 months they have stopped accepting US dollars and reverting to there own currencies, at the moment it is impossible to return to Phnom Penh because for every $1000 aud I only get $650 in usd , is the government considering to rid themselves of the usd and float the riel and or start trading in the Chinese yuan, maybe it is better to take aud and exchange it for the riel in Cambodia.