Cuban authorities say a new constitution has been approved by nearly 87 percent of voters, a relatively low figure for a country where official proposals routinely receive higher than 90 percent approval.

The heads of Cuba's National Electoral Commission said 7,848,343 people voted Sunday on a new constitution that preserves the single-party socialist system and centrally planned economy while updating some financial, electoral and criminal laws.

Some 300,000 votes were counted as invalid because they were blank or defaced. And 706,400 people voted against the new constitution.

Cuba's President Miguel Diaz-Canel and his wife Lis Cuesta wait at a polling station during a referendum to approve or reject the new constitution in Havana, Cuba, Sunday, Feb. 24, 2019. The constitutional reforms maintain Cuba's single-party political system and centrally planned economy while recognizing private property and small businesses, which have been part of the island's economy without formal legal status for more than a decade. (Fernando MedinaPool Photo via AP)

Cuba's President Miguel Diaz-Canel and his wife Lis Cuesta wait at a polling station during a referendum to approve or reject the new constitution in Havana, Cuba, Sunday, Feb. 24, 2019. The constitutional reforms maintain Cuba's single-party political system and centrally planned economy while recognizing private property and small businesses, which have been part of the island's economy without formal legal status for more than a decade. (Fernando MedinaPool Photo via AP)

The commission said 6,816,169 people voted in favor of the new charter. The current constitution was approved by 97.7 percent of voters in a referendum in 1976, the peak of a system dedicated to displays of national unity.