A court in northern Tunisia handed one-month jail terms on Thursday to four men for eating in public during Ramadan, a spokesman said.

The four had been "eating and smoking in a public garden, a provocative act during Ramadan", which started last week, Chokri Lahmar, prosecution spokesman at the court in Bizerte, told AFP.

He said the four men had 10 days to appeal against their one-month sentences before the terms take effect.

Their sentencing, which followed complaints from other local residents, comes ahead of a call circulated on social media for a 11 June demonstration to protect the rights of those who decline to take part in the Ramadan fast.

Although the state has the role of "guardian of religion" under the constitution, Tunisia has no specific law banning eating in public during Ramadan, a controversy which resurfaces each year in the North African country.

Most restaurants and coffee shops remain shut in Tunisia during daylight hours over the holy month, but some establishments open behind closed curtains to prevent customers from being seen.