WASHINGTON — The Senate broke Friday for a two-week recess without approving an extension of jobless benefits after Republicans blocked the $9 billion measure, saying it would add to the federal deficit.

Jobless benefits begin running out April 5. Although the extension will be taken up when the Senate returns April 12, nearly 1 million unemployed people could be affected if the benefits are not restored by the end of April, according to the National Employment Law Project. COBRA health insurance subsidies to the unemployed expire Wednesday.

Democrats said they will seek to provide benefits retroactively to those who lose them, and they attacked Republicans for blocking the extension, already approved by the House. Republicans blamed Democrats for refusing to agree to spending cuts to pay for the assistance.

The congressional inaction on jobless benefits came on the same day that the U.S. Department of Labor reported that California’s unemployment rate for February held steady at 12.5 percent as the recession lingers.

In the immediate future, the lack of approval is expected to have a limited effect on the 1.5 million Californians currently claiming unemployment benefits, according to a spokeswoman for the state Employment Development Department.

But the effects become much greater if Congress fails to act when it returns.

“For the vast majority, there is at least some kind of short cushion there for them until Congress comes back on April 12,” said spokeswoman Loree Levy.

Sen. Carl Levin, D-Mich., whose state has the nation’s highest unemployment rate of 14.1 percent, called the inaction “inhumane.”

Sen. Sherrod Brown, D-Ohio, read on the Senate floor a letter from an out-of-work constituent: “As much as I wish I didn’t have to collect unemployment, I am terrified that it will run out.”

But Sen. Tom Coburn, R-Okla., said, “No one in America, outside of a few politicians in Washington, believes the federal budget is running at peak efficiency and can’t be trimmed to pay for important priorities like unemployment benefits.”

The fight comes after Sen. Jim Bunning, R-Ky., earlier this month single-handedly held up extensions of unemployment and COBRA benefits over concerns that the bill would increase the federal deficit.

Republicans suggested that unspent economic stimulus funds be tapped, but Democrats said the money is needed to create jobs.

More than 11 million jobless workers are collecting some form of unemployment insurance, including nearly 5.7 million receiving extensions, according to the National Employment Law Project.