WASHINGTON (Reuters) - The Senate voted on Saturday to extend a payroll tax cut for two months in legislation that also attempts to force President Barack Obama to approve construction of an oil pipeline.

The Senate overwhelmingly passed the legislation by a vote of 89-10. It is expected to be voted on by the House of Representatives next week, and if approved, will then go to Obama for his signature.

The measure also would extend long-term unemployment benefits for another two months.

The Senate is expected later Saturday to finish voting on a $915 billion bill to keep many U.S. government agencies operating through next September. The House on Friday passed this measure.

Obama is expected to also sign this bill into law promptly.

The payroll tax cut extension contains a provision many Democrats, including Obama, had opposed. It attempts to speed approval of construction of the Keystone XL oil pipeline from Canada to Gulf of Mexico facilities in Texas.

(Reporting By Richard Cowan, Rachelle Younglai)

Mochila insert follows.