Cobra Gold, the largest military drill in Asia, will be a massive exercise this year with a total of 28 participating countries.
The intensity and number of activities of the drill has increased even though the US keeps scaling back its armed forces, defence sources say.
Citing a Royal Thai Armed Forces document on the 35th instalment of Cobra Gold, which will start on Feb 9 and last 11 days, the sources said a total of 8,564 military personnel from seven countries will take part in the drill.
They consist of 4,286 officers from Thailand, 3,288 from the US, 327 from Japan, 51 from Singapore, 32 from Indonesia, 387 from Korea and 133 from Malaysia.
The nations invited to be part of the Multinational Planning Augmentation Team include Australia, Canada, France, the United Kingdom, Italy, Bangladesh, Nepal, Mongolia and the Philippines.
Ten countries will take part as the Coalition Observer Liaison Team. They comprise Chile, Vietnam, Laos, South Africa, the United Arab Emirates, the Netherlands, Brunei, Myanmar, Saudi Arabia and Cambodia.
Two other countries -- China and India -- will join the extra session for providing humanitarian and disaster assistance.
Under the exercise, Malaysian military personnel will join the air mobile operations, according to the sources. Singaporean officers will take part in the operation to rescue civilians from conflict areas and live fire exercises.
Japanese personnel will join a drill to evacuate people from conflict zones, while Korean officers will engage in amphibious assault exercises, civilian evacuation from conflict zones and live fire drills.
The objective of the exercise is to foster militarily ties among the countries involved, enhance the capacity in the joint military operation and practice guidelines for multinational forces.
Following the 2014 coup, the US army substantially scaled back its Cobra Gold personnel from more than 8,000 in previous years to 3,700 last year.
Section 508 of the Foreign Assistance Act, a US law first enacted in 1961, says the US must cut aid to any country "whose duly elected head of government is deposed by military coup or decree".
However, Thai military sources confirmed the upcoming exercise will be intense.
The key events include command post and field training exercises, humanitarian civic assistance, combined arms live fire exercises as well as non-combatant evacuation.
Based on the field training exercise, an amphibious demonstration will be carried out in the navy base at Had Yao Beach in Chon Buri on Feb 12. Thai, South Korean and American military personnel will participate.
The combined arms live fire exercise will be held at the navy base in Ban Chanthaklem in Chanthaburi's Khao Kitchakut on Feb 19 for which Thai, American, Korean and Malaysian personnel will take part.
The non-combat evacuation will be undertaken at the Royal Thai Naval Air Division in Rayong on Feb 19. Thai, American, Japanese, Korean and Malaysian officers will participate in the event.
A senior leaders seminar will also be held on Feb 9 to boost the relationship of generals in the key seven participating countries. The opening ceremony will be held in Chon Buri.