Tunisians have voted in favor of a new constitution that would give far more power to President Kais Saied.

The proposed constitution, which was put to a referendum on Monday, says the president can appoint a prime minister without parliamentary approval.

It also says political power will be exercised solely by the president, not by Parliament, as it is now.

Preliminary results announced on Tuesday show that 94.6 percent of votes back the new charter. But voter turnout stood at just 30.5 percent.

Opposition parties and labor unions had been calling for a boycott of the vote. They say the low voter turnout shows registered voters opposed the referendum.

They say they cannot accept the outcome of the vote.

Saied has been consolidating his grip on power since taking office three years ago. He suspended Parliament and took other high-handed steps under the pretext of ending political and economic turmoil.

Tunisia is viewed as the only successful example of the Arab Spring pro-democracy movement after the nation's former autocratic government collapsed in 2011 following public protests.

But concerns are on the rise that the North African country may be swept further into political turmoil.