Puerto Rico's governor has signed a bill that allows certain public agencies to buy up to $400 million in tax and revenue anticipation notes.

Alejandro Garcia Padilla said Friday that the bill aims to help boost the liquidity of the U.S. territory's Treasury Department amid an economic crisis. Such notes are usually repaid with upcoming tax collections.

Puerto Rico's Government Development Bank will oversee a fund for revenue generated by the notes. The government can access the fund if the Treasury Department's monthly revenue forecasts exceed collections.

The announcement comes just days after Garcia said the island's $72 billion public debt is unpayable and that he would seek a payment moratorium from bondholders.

The island is struggling to emerge from a nearly decade-long economic slump.