Thousands of Yemenis are protesting in the port city of Aden, pushing for the southern part of the country to break away from the North.
Some southern Yemenis are angry at what they see as the monopoly of the North over power, wealth and natural resources.
South Yemen was once an independent state between 1967 and 1990 before it merged with the North. Four years later, the South tried to split away again, but was defeated after a short-lived but bloody civil war.
The current Southern movement was launched in 2007 and it includes both peaceful protesters and armed groups.
Al Jazeera's Hashem Ahelbarra, reporting from Aden, said that the number of protesters at the Independence Square on Sunday had grown and many were expecting the southern leader, Hassan Baoum to make an appearance.
"The problem that they face is that they are widely divided politically," he said, adding that there was no agreement among the groups as to who would be the next leader if they did split from the North.
"Today they are starting with a symbolic move to press ahead with separatist demands."
Ahelbarra said that even though Yemen's President Yemeni Abd Rabbu Mansour Hadi and Prime Minister Khaled Bahhah were both from the South, many were still nostalgic for one of the last leaders of South Yemen, Ali Salim al-Beidh, who is currently in Germany and plans to return soon.
"It remains quite delicate. One of the problems the secessionists face is the international community is not convinced that this state could be a viable one because they know the secessionists are weak.". He said there were also fears that al-Qaeda would take over the south if it broke away.
Source: Al Jazeera