The secretary general of the Pacific Islands Forum, Tuiloma Neroni Slade, says the trade in service arrangements under the Pacific Island Countries Trade Agreement, or PICTA, have been agreed to.
He told trade ministers meeting in Tonga he is very pleased to announce the milestone.
Mr Slade says this is a crucial step in strengthening the regional economy and members must take advantage of the opportunities being made available.
PICTA seeks to strengthen, expand and diversify trade between Forum countries through the elimination of tariff and non-tariff barriers.
While a number of countries already have preferential arrangements in place for trade in goods, there has been an effort for several years to extend PICTA to include trade in services, such as improved labour mobility.