Congress MPs, State Ministers and other leaders from Seemandhra, opposed to division, attended the 'Chalo Hyderabad' protest organised at Indira Park by the Andhra Pradesh Non-Gazetted Officers' (APNGOs) association.
The sit-in comes at a time when the AP legislature were debating the draft Andhra Pradesh Re-organisation Bill, which envisages creation of a separate Telangana.
The President has given the legislature time till January 23 to return the Bill after due deliberations, though the AP Government has sought four more weeks to discuss it.
Last year, Government employees from Seemandhra, who have been in the forefront of the agitation against the bifurcation of Andhra Pradesh, had organised a strike lasting for over two months.