Which country is the smallest sovereign state in the Caribbean with two inhabited main islands?

Saint Kitts and Nevis is the smallest sovereign state in the Caribbean with two inhabited main islands.

The country is a federation of Saint Kitts and Nevis, both of which have permanent communities and their own distinctive geography. Saint Kitts contains the capital, Basseterre, while Charlestown is the principal settlement on Nevis.

Saint Kitts is the larger island and is dominated by Mount Liamuiga, a volcanic peak. Nevis is centred on Nevis Peak. The islands are separated by The Narrows, a channel only a few kilometres wide.

Several Caribbean countries are archipelagos, but this question identifies a sovereign federation whose two principal inhabited islands form the entire country. Antigua and Barbuda and Saint Vincent and the Grenadines include additional islands, while Trinidad and Tobago is substantially larger.