Centre director Chalerm Yubamrung warned demonstrators not to invade government offices as they will be defended by security authorities.
"I will definitely not use force except when protesters storm inside government offices," he told a press conference at the Labour Ministry.
The caretaker labour minister has been appointed the centre chief to oversee the enforcement of the emergency decree, which took affect on Wednesday in all areas in Bangkok and Nonthaburi. It includes Bang Phli district in Samut Prakan province and Lat Lum Kaeo district in Pathum Thani.
Mr Chalerm assigned National Security Council chief Lt Gen Paradorn Pattanatabut and Department of Special Investigation chief Tarit Pengdith as his key men in implementing the decree.
His press conference followed a temporary blockade of the ministry by the People's Democratic Reform Committee (PDRC).
Mr Chalerm said he held no grudge against the protesters but called on them to respect the rights of other people.
Mr Tarit said the centre will issue a statement directed at PDRC leader Suthep Thaugsuban to bring back "happiness" to people in Bangkok.
The centre has two offices at the National Police Office and the office of the Defence Ministry's permanent secretary at Muang Thong Thani, said caretaker Deputy Prime Minister Surapong Tovichakchaikul, who is the centre chief advisor.