A protest against Prime Minister Prayut Chan-o-cha in a foreign country would hurt Thailand's reputation, the government warns.
Speaking at Government House Wednesday, spokesman Maj Gen Sansern Kaewkamnerd said a protest by an anti-government group against Gen Prayut in the US would tarnish the country's image.
The action would also hurt Thai people's feelings, he added.
Gen Prayut will attend the 70th Regular Session of the UN General Assembly (UNGA 70) at the UN Headquarters in New York City between Sept 23 and Oct 1, according to Maj Gen Sansern.
He is expected to address the assembly which will be attended by many of the world's leaders.
"No one loves Thailand more than Thai people," Maj Gen Sansern said, calling on anti-government groups who plan to stage a protest against the premier to call off their plan.
The government was tipped off that an anti-government group would stage a protest against the premier when he is in the US for the gathering, he said.
Human rights groups upset at the military's recent detention of critics have warned the government could face criticism from overseas governments and media outlets at the general assembly.
Maj Gen Sansern said Gen Prayut is concerned protests against him would create misunderstanding among foreigners. People are free to express themselves but it should be done in a positive way, Maj Gen Sansern said.
He also thanked those who plan to give morale support to Gen Prayut in New York.
Maj Gen Sansern urged the public to understand the government and the National Council for Peace and Order has worked hard to restore peace and move the country forward.
He also urged Thai people to support the government's plans and cooperate.
Maj Gen Sansern said ambassadors have an understanding of what the government has done for the country.
Meanwhile, Gen Prayut told the media Wednesday he would address two main topics in New York: ways to tackle poverty; and the promotion of sustainable development to ensure economic growth, social protection and the preservation of Thailand's environment.
The premier confirmed he doesn't plan to speak about the country's reform roadmap at the UN.
It's not yet known if he intends talking to foreign reporters when he is in the US. "I will give interviews to them if I have time," Gen Prayut said.
Gen Prayut said the government will work harder to move the country forward and return it to democracy as soon as possible.
The premier wants foreigners to view Thailand as a fast-growing country and not as a fragile, unstable and conflict-affected state.
Each country has its own political culture which affects different political processes, Gen Prayut said.