
Acting National Police chief Wichien Pojphosri said leaders of the two groups were told to ensure that their supporters would not stray out of their areas to avoid clashes.
Wichien expressed confidence that police could control the situation as the red-shirt leaders had been briefed about the proper procedure for submitting the petition.
Wichien was speaking to reporters before chairing a meeting at Metropolitan Police headquarters on keeping law and order during the rallies today. Metropolitan Police chief Lt Gen Worapong Chiewpreecha, superintendents of all police stations in Bangkok, senior military officers and other officials attended.
He said he was confident that no one would like to stir up violence.
Police disagreed with the filing of the petition because it would involve a lot of demonstrators, but the Office of His Majesty's Principal Private Secretary had already made preparations, he said.
Office representatives would receive the documents outside of the Wiset Chaisri Gate at the Grand Palace while police would provide security in the area.
The office would prepare containers for keeping the petition documents and police would carry the documents into the Grand Palace for the office.
Traffic would be allowed on Rajdamnoen Nai Road while Na Phra Larn Road and the road in front of Wiset Chaisri will be blocked to traffic.
Police would also have to clear traffic for Her Royal Highness Princess Maha Chakri Sirindhorn to travel to her workplace at the Suan Kularb Throne Hall.
Police had coordinated with the leaders of the blue shirts, who would gather in front of the Supreme Court, to make sure that their people would not leave the rally ground.
Sanam Luang and the Supreme Court are located nearby so both sides were told not to move out of their areas, Wichien said.
About 50 police would be deployed to guard Wiset Chaisri. In case violence broke out, reinforcements could be called immediately.
Internal Security Operations Command Area 1 has prepared five companies of soldiers to assist police in keeping law and order while police have assigned 10 companies for the task.
The police personnel will come from Provincial Police regions 1, 2 and 7 as well as the Central Investigation and Border Patrol police forces.
"We will have enough police personnel and may not need to use the prepared military forces," Wichien said.
The Supreme Court's Criminal Division for Political Office Holders has requested Chana Songkram Police Station to deploy officers to protect the courthouse, as many people, especially Newin's supporters, would gather there to hear its ruling.