Wal-Mart’s proposed buy of Puerto Rican supermarket chain Supermercado Amigo has run into trouble as the local government said it will attempt to block the acquisition.

Justice secretary Anabelle Rodriquez said the government would take action to invalidate the purchase of the 35-strong supermarket chain.

The Puerto Rican government is reported to be worried that the acquisition, reported to be worth $225m, would violate the island’s anti-trust laws.