(Adds details on bond sale, proposed oil tax hike)
Nov 26 (Reuters) - Puerto Rico's public transit system will shut down on Monday if lawmakers do not increase a tax on oil, the U.S. commonwealth's Government Development Bank said, in what would be a major escalation of the island's debt crisis.
The possible shutdown of Puerto Rico's buses and commuter train services threatens a fragile economy and would be a further blow to residents already facing budget cuts.
"The HTA (Highways and Transportation Authority) does not have sufficient income or liquidity to meet its payroll obligations for December," the bank said in a statement. "Given this fiscal picture, as indicated by the governor, public transport services will close next Monday."
Without proceeds from a bond sale that the oil tax hike is intended to back, the island could also lack the liquidity to meet government emergencies in 2015, the GDB said in a statement on Wednesday. It has contingency plans to postpone loans for public works and stop disbursement of municipal and government loans, it said.
Governor Alejandro Garcia Padilla has been unable to convince enough members of his own party to back a 68 percent increase to a tax on crude oil, which was expected to be passed last week. He convened a special session of the legislature on Monday, but lawmakers called a recess until Dec. 1.
Puerto Rico has delayed a bond sale of up to $2.9 billion until early 2015 which it had been aiming to complete this year using the proceeds of the oil tax increase. The government planned to increase its tax on crude oil to $15.50 per barrel from $6.25 to raise $178 million a year to back the bonds.
Reporting by Edward Krudy in New York; Editing by Chris Reese and Lisa Shumaker