As the Senate prepares to open debate on a comprehensive immigration overhaul next week, the GOP-held House has voted to halt the Obama administration's policy of deferring deportation of young adults brought to the country illegally as children.

The House rejected the policy as an amendment to an appropriations measure for the Department of Homeland Security. It is unlikely to become law -- appropriations measures must be negotiated with the Senate, which will resist the amendment.

But the 224 to 201 vote, which broke along party lines, is an ominous sign for the future of immigration reform efforts. Efforts to normalize the status of so-called DREAMers have been the most consistently popular parts of changes to immigration law.

Republicans have opposed the Obama policy since he introduced deferred deportations in June 2012. They argued the president overstepped his authority by unilaterally halting deportations, and the issue should be handled by Congress instead.

But the vote is sure to anger the immigrant groups that Republicans have sought to woo since their November election loss and may be a sign that Republicans believe the political imperative for immigration changes is waning.

To qualify for deferred deportation under Obama's policy, young adults had to have come to the country before the age of 16 and be high school graduates or served in the military. They must have clean criminal records.

The amendment was offered by Rep. Steve King (R-Iowa), one of the most consistent opponents of efforts that would lead to normalizing the legal status of the estimated 11 million people now in the country illegally.

The vote came as Sen. Marco Rubio (R-Fla.), a key proponent of changes, has warned a bipartisan bill he helped author cannot pass the Senate without additional border security measures. And Rep. Raul Labrador (R-Idaho), key member of a bipartisan House group that has been working to introduce a bill for four years, dropped out of the effort.

Rep. Luis V. Gutierrez (D-Ill.), another member of the group, said the remaining seven members of the group -- who include four Democrats and three Republicans -- will press forward and introduce a bill in coming weeks.

"We are still in the early stages of a very long process of getting our immigration system overhauled," he said.