By Jim Wolf

WASHINGTON (Reuters) - The U.S. senator leading a drive to persuade President Barack Obama to disregard Beijing's concerns and sell new F-16 fighters to Taiwan faulted the island for what he said was a failure to push hard enough for the planes.

"When it comes to Taiwan's military capabilities, there seems to be a puzzling sense of complacency in Taipei," said Senator John Cornyn.

Cornyn, a Texas Republican, is responsible for rounding up his party's votes in the Senate. He has sought to force the Obama administration to sell Taiwan the 66 F-16C/D models it has sought in the past. The planes are produced at a Fort Worth, Texas, plant by Lockheed Martin Corp.

Cornyn voiced disappointment that Taiwan "seems to have backed off of its pursuit for new F-16s." Taipei has agreed to a U.S. offer to upgrade its fleet of 145 older-model F-16 fighters as part of a projected $3.7 billion deal.

"Without aggressive and consistent advocacy by Taiwan for its own interests, it will be nearly impossible for its friends in Congress to push through the sale of F-16s or other advanced weapons," he said in remarks read in his absence at a panel discussion Friday at the Heritage Foundation, a conservative research group.

The office that represents Taiwan's interests in Washington did not immediately respond to a request for comment.

Both the George W. Bush and Obama administrations have held off on Taiwan's standing request for new F-16s amid warnings from China, which deems the self-ruling island a rogue province subject to return to its fold, by force if necessary.

Taipei must find the political will to boost Taiwan's defense budget, Cornyn said in his statement. He said it had been cut each year from 2009 through 2011.

"Taiwan's leaders also need to stop allowing themselves to be bullied by the Obama Administration," he said.

Some Taiwan officials have shown interest in leapfrogging the F-16C/D models to buy Lockheed Martin's next-generation, radar-evading F-35 Joint Strike Fighter. The F-35 is in early production.

Cornyn has used his senatorial powers twice in past two years to delay consideration of Obama's nominees for senior jobs at the U.S. State Department and Defense Department in an effort to push the sale of new F-16s.

(Reporting By Jim Wolf; Editing by Todd Eastham)