A key committee in the Republican-held US House of Representatives voted Thursday to force the White House to turn over internal communications related to now bankrupt solar panel firm Solyndra.

The House Energy and Commerce Subcommittee on Oversight and Investigations Subcommittee voted strictly along party lines, 14-9, to authorize subpoenas for the documents, an escalation in a months-long political battle over the company.

Republicans contend that President Barack Obama's administration may have improperly influenced the US Energy Department's decision to give the firm a $535 million government loan guarantee.

The White House denies any wrongdoing, and Democrats have charged that the Republican-led investigation, launched in March, aims to embarrass the president and derail his efforts to boost clean-energy projects in the United States.

House Energy and Commerce Committee Chairman Fred Upton called the subpoena a "last resort" and described getting key documents from the Obama administration as "like extracting a tooth without anesthesia — unnecessarily painful and time-consuming."

"This is not about using our subpoena power, this is about fossil fuel and nuclear interests wanting fewer Americans using solar power," said Representative Ed Markey, a key member of the committee.

California-based Solyndra filed for bankruptcy in September, closed its doors and laid off 1,000 workers, leaving taxpayers on the hook for the loan.

US Energy Secretary Steven Chu will testify before the subcommittee on November 17.

The vote came one day after Upton and another senior Republican, as well as two top Democrats, met with White House Counsel Kathryn Ruemmler in a failed bid to forge an agreement that could avoid the subpoena.

It was not clear whether the White House would comply with any subpoena for internal communications, something administrations of both US political parties have typically resisted fiercely.

The White House last week ordered a probe into US government loans to clean energy firms.