Cuba says it will legalize small and medium-sized private businesses, a move that could significantly expand the space allowed for private enterprise in one of the world's last communist countries.

Communist Party documents published Tuesday say a category of small, mid-sized and "micro" private business is being added to the party's master plan for social and economic development.

Until now, the government has allowed private enterprise only by "self-employed" workers in several hundred established categories. In reality, many of those workers have become small business owners employing other Cubans. But many complain about the difficulties of running a business in a system that does not officially recognize them, and that often engages in crackdowns on successful businesses for supposed violations of the arcane rules on self-employment.