Prime Minister Srettha Thavisin will start his five-day trip to Hong Kong and three Asean countries on Sunday.
The premier will depart from the Royal Thai Air Force's (RTAF) terminal at Don Mueang Airport aboard the force's Airbus 320 aircraft bound for Hong Kong.
After Hong Kong, the premier will visit three Asean countries -- Singapore, Brunei and Malaysia -- before returning home on Thursday.
Regarding his Asean trip, Mr Srettha told reporters the visit is aimed at tightening diplomatic relations with those countries and strengthening cooperation in various areas.
The premier has also scheduled other overseas trips in the coming months to places such as the United States for the Asia-Pacific Economic Cooperation summit next month as well as Japan and China.
Mr Srettha's trip to China is scheduled for the middle of this month, said Deputy Foreign Affairs Minister Jakkapong Sangmanee.
The premier's agenda in Beijing includes talks to rebuild confidence in tourism in Thailand in the wake of the Oct 3 Siam Paragon shopping mall shooting that killed two people, including a Chinese tourist, he said.
Earlier, Foreign Affairs Minister Parnpree Bahiddha-Nukara said Mr Srettha will also discuss a possible solution in the wrangle over a German submarine engine with the Chinese government.
Germany has refused to allow its MTU396 diesel engine to be fitted in a Chinese submarine Thailand has commissioned, he said.
Meanwhile, more flights from China will land on the resort island of Phuket during the high tourist season in the coming months, according to Phuket International Airport's director-general, Monchai Tanode.
Many airlines have booked their slots to fly to Phuket during peak tourism period starting next month, bringing traffic to between 80% and 90% of the pre-pandemic levels, he said.
Last month, most visitors who arrived by air to Phuket were from China (44,680), followed by Russia (41,180), Australia (22,897), India (19,127) and Malaysia (14,290), he said.
Despite the current low tourist season, the number of visitors from most countries has started to recover, he said.
On average, the number of visitors from countries whose nationals traditionally travelled to Phuket in high numbers is now back to 70% of pre-pandemic levels, said Mr Monchai.
The number is expected to jump to 87% during the high tourism season, he said.
Due to the expected heavy airport traffic, Phuket airport will operate around the clock during the high season, he said, adding the airport underwent renovations at night during the pandemic.
He said the airport has earmarked 6 billion baht for renovating its international terminal to help welcome 18 million visitors a year.