PARIS (AP) _ Mexico was invited formally Thursday to become the first developing nation to join the Organization for Economic Cooperation and Development.

The 24-member group confirmed last month that Mexico would be its first new member since New Zealand joined in 1973.

The Paris-based organization, which includes the United States, Japan and the world's other leading industrial nations, promotes trade and investment among members and helps coordinate aid to poorer countries.

Mexico's gross domestic product of $360 billion in 1993 will make it the ninth-largest OECD economy, just smaller than Spain and slightly larger than the Netherlands.

But with a population of 86 million, the third largest of the OECD nations, Mexico's per capita economic output ranks near the bottom of the group.

The OECD said Mexico would become a full-fledged member in a few weeks, after completing domestic ratification of the agreement.