Tonga's prime minister, Lord Tu'ivakano, is representing the country at a NATO summit - the first time the country has attended such a meeting.
Two years ago Tonga began deploying troops as part of the NATO force in Afghanistan.
Radio Tonga reports that the summit in Chicago will include discussions on Afghanistan and its future, how countries can be secure when budgets are being cut, and how NATO can develop its network of partnerships.
Following that meeting, the prime minister will travel to Japan to take part in the sixth Pacific Islands Leaders Meeting.
