Washington ? The House voted Thursday to extend $1,000 child tax credits through the rest of the decade, leaving uncertainty whether low-income families will cash in on rebates going out to other households this summer.

The 224-201 vote on the package of $82 billion in new tax cuts extends the $1,000 child tax credit to 2010 and makes the benefit available to more low-income families and higher-income married couples. It also sets up a confrontation with the Senate, which a week ago passed a much smaller bill to allow 6.5 million low-wage households to qualify for the checks of up to $400 per child that will be mailed to middle-income parents.

Democrats said House Republicans omitted instructions telling the Treasury Department to send child credit refunds this year to low-income families, leaving those families to claim the bigger credit next year when they file their tax returns. “This is one of the most cynical and hypocritical moves I have ever seen,” said Charles Rangel of New York, the top Democrat on the Ways and Means Committee.

House Republicans said the bill didn’t block the Treasury Department from issuing checks to low-income families later this year, leaving the possibility that the final version negotiated between the House and Senate will include rebates for those families this fall.

“We intend to get these checks out as quickly as possible,” said John Feehery, spokesman for House Speaker J. Dennis Hastert, R-Ill.

House Ways and Means Committee Chairman Bill Thomas, R-Calif., said when the House and Senate meet to hammer out their differences, “obviously that would be one of the issues.”

Thomas criticized Democrats for ignoring the bill’s benefits for all working families with children. “Sadly, rather than focusing on the merits of this legislation, some have used this as a political opportunity,” he said.

A House Ways and Means Committee aide, speaking on condition of anonymity, said committee members made a practical decision not to write in instructions for Treasury to send advance refunds and allow low-income families to claim the bigger refund in 2004.

They did not want to delay checks already scheduled to go to 25 million families, and a second round of checks would be costly and burdensome to the Internal Revenue Service.

The House also removed from a Senate-passed bill language that would have enabled families of servicemen and servicewomen who served in the war with Iraq to claim bigger child tax credits.

The White House said Thursday it wanted the House and Senate to “quickly resolve their differences.”