The message was communicated at the NCPO's weekly briefing of foreign military attaches at army headquarters in Bangkok on Wednesday.
Maj Gen Panot Saengtien, director of army intelligence, told the meeting that he did not think any foreign government would support an overseas movement against the NCPO, especially the group organised by former Pheu Thai party leader Charupong Ruangsuwan.
Giving support to such a dissident movement would be viewed as an intervention in the internal affairs of Thailand, he said.
Maj Gen Panot also said the NCPO had adequate evidence linking former PM's office minister Jakrapob Penkair to the illegall possession of weapons, and to revoke the passports of and seek arrest warrants for some red-shirt movement leaders.
Mr Jakrapob is a key figure in the anti-NCPO Seri Thai movement headed by Mr Charupong. Both men are believed to have fled and to be living abroad.
The military attaches were told that a provisional constitution would be finished this month and a new permanent charter would be ready by July next year and be promulgated the following month. Then a general election would be called next year to restore democracy in Thailand.
Representatives of 25 countries attended the briefing, including from Ukraine, Brunei, Nepal, Bangladesh and Israel, which do not have military attaches in Thailand.