The purpose of the Tri-partite Agreement was to enable Nepalese citizens to be recruited into the armies of Great Britain and India and to ensure that each country could recruit and maintain formed Gurkha regiments on an equal basis.
At the same time the TPA safeguarded the cultural, religious and ethnic heritage of Gurkha soldiers to satisfy the wishes of the Nepalese Government. These arrangements reflected concerns at the time about whether the newly formed Indian Army would be able to retain or attract Gurkhas if there were significant differences between the British Brigade of Gurkhas and Indian Army terms and conditions of service (TACOS).
There was also a concern about creating differences in Nepal where British Gurkha pensioners continued to live alongside fellow citizens who served in the Nepalese and Indian Armies.
The TPA laid down principles which are the foundation of Gurkha service in the British Army. Importantly, that Gurkhas were recruited as Nepalese citizens into formed units in the British Army and that when they completed their service were returned to Nepal.
Also, that basic Gurkha pay and pensions remained linked to Indian Army TACOS. These principles were enshrined in the TPA, the foundation of which is the mutual goodwill that exists between the countries concerned.
The British Government did not wish to undermine this by stepping outside the terms of the TPA or acting in a way that could impact on the ability to recruit Gurkhas from Nepal. It is for this reason that successive Governments have always honoured their obligations to the Nepalese and Indian Governments under the TPA, and acted in accordance with the principles that underpin it.
Without the TPA, Nepalese citizens could not be recruited into the British Army. This is of fundamental importance because it means that without the TPA there would be no Brigade of Gurkhas, and Gurkha soldiers would not be able to serve in the British Army.