The overall turnout was 57.61 per cent, narrowly missing the government's expectation of around 60 per cent and well below turnout at previous general elections.
Many urban Thais, especially in Bangkok, overwhelmingly backed the constitution with many saying the new charter was the best way to swiftly end the political turmoil and military rule.
Bangkok had been the centre of months of street protests last year in the run-up to Thaksin's ouster.
|The charters received strong support in the |
south of Thailand [GALLO/GETTY]
But a resounding "No" in the northeast - the poorest part of the country and a Thaksin stronghold - suggests that in a large swathe of the country the coup leaders' efforts to discredit the exiled former leader had failed.
Thaksin's opponents had accused the billionaire businessman of corruption and abuse of power.
His supporters though say the coup was a move by the urban elite to restore influence lost to the rural majority under Thaksin.
The military-backed constitution, Thailand's 18th in 75 years of on-off democracy, is designed to prevent a repeat of Thaksin's powerful single-party style of government.
Opponents say the new charter will roll back democratic reforms and entrench the power of the military, the palace and the bureaucracy while weakening elected leaders.
Human rights groups have criticised the poll as a sham, given that nearly half of Thailand's 76 provinces remain under martial law and that a "No" vote would have allowed the army to impose any one of the previous 17 constitutions.
Surayud Chulanont, Thailand's military-installed prime minister, said that in the wake of the referendum elections will "definitely be held at the end of the year", hinting at a date after the king's birthday on December 5.