In her letter, Gandhi has cited that many countries including India prohibit the export of monkeys for use in animal experiments or for other purposes.

'Medical authorities, including the US National Research Council, are calling for a shift away from using animals in testing toward non-animal research strategies,' Gandhi wrote.

'Puerto Rico can help lead the way to safer pharmaceuticals, improved human health and a world free from cruelty to animals by taking one small but significant first step-shutting down any further construction of the Bioculture monkey facility.'