She denied the planned mass rally had been postponed or cancelled.
Ms Tida, however, did not disclose the venue or venues for the rally.
She said of the target attendance of 500,000, at least 200,000 would be from the Northeast, 100,000 from the Central, East and West regions, and 100,000 from the South. These 400,000 red shirts had already registered with their core leaders to confirm their attendance. The rest are expected to be other people who will come on their own.
Ms Tida denied former Samut Prakan MP Worachai Hema's remark that the red shirts would gather at 20 spots, each with 20,000 attendants, around Bangkok and nearby provinces.
The former UDD chair said to prepare for the April 5 rally the red shirts had held a meeting at three locations. Those from the North met in Phitsanulok while the red shirts from the Northeast met in Roi-et. Those from Bangkok and the Central, East and West met in Ayutthaya.
At the meetings, UDD core members were told to be prepared for a political struggle and to strengthen their political bases, particularly to cope with a possible military coup, she said.