Thousands of anti-government demonstrators were heading to central squares in at least 17 cities in Yemen on Friday to call on President Ali Abdullah Saleh to go, DPA reported.
The "Friday of Determination" comes after Qatar withdrew from a Gulf-brokered initiative aimed at resolving the unrest in Yemen, criticising the delay in signing the deal and the continued violence.
The president's supporters also gathered from different provinces in the capital to show solidarity with the president, in what they dubbed a "Friday of Unity" to call on him to stay in office until his term ends in 2013.
The six-nation Gulf Cooperation Council (GCC) has offered to mediate in the crisis in neighbouring Yemen with a deal that would set a timetable for Saleh to leave office and grant legal immunity to him, his family and aides.
Saleh, a key US ally, has refused to sign the deal and remains defiant despite growing pressure from the GCC to transfer power to his deputy. The Gulf proposal would allow him to remain head of the ruling party.
Protests erupted in Yemen in January and grew more strident in February after the fall of Egyptian leader Hosny Mubarak. The death toll exceeds 150, according to rights groups.
The Gulf Cooperation Council is made up of Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates.