Venezuelan President Nicolás Maduro on Tuesday directed the country’s state-owned companies to “immediately” begin to explore and exploit the oil, gas and mines in Guyana’s Essequibo region, a territory larger than Greece and rich in oil and minerals that Venezuela claims as its own.

The announcement came a day a day after Maduro got the victory he sought in a weekend referendum on whether to claim sovereignty over the region.

Maduro said he would “immediately” proceed “to grant operating licenses for the exploration and exploitation of oil, gas and mines in the entire area of our Essequibo.” He also ordered the creation of local subsidiaries of Venezuelan public companies, including oil giant PDVSA and mining conglomerate Corporación Venezolana de Guayana.