The Central Election Commission in Armenia announced on Monday that 63.35 percent of voters cast their ballots in favor of constitutional changes during Sunday's referendum, with voter turnout at around 50 percent.

The amendments to the constitution will shift the president's powers to the prime minister, and make the head of state a largely ceremonial figure.

The changes will also give the power to elect the president to the parliament, instead of by popular vote.

'Treason'?

However, observers from the Council of Europe's Parliamentary Assembly (PACE) said that the low voter turnout was a sign that "the referendum was driven by political interests instead of the needs of the Armenian public and was perceived by many citizens as a vote of confidence in the government."

The right group also said that there were several voting irregularities and violations, including inaccurate voting lists, and allegations of organized vote buying.

"The delegation urges the authorities to address these issues in order to build trust in the voting process and in politics in general to ensure a genuinely democratic future for Armenia," the observers said in a statement.

Opposition figures also criticized the referendum, saying that it was a ploy for Armenian President Serzh Sarksyan to stay in power after his second term ends in 2018.

"What happened yesterday during the vote is a treason," said opposition leader Raffi Hovannisian at a protest in the capital on Monday.

The opposition has promised mass protests, although only about 500 people turned up on the streets of Yerevan on Sunday night, demanding any results be annulled.

The constitutional amendments will come into force in May 2017.

ls/cmk (AP, AFP, Reuters)