Terrorist attacks by Islamic fundamentalists in Paris and Sydney have raised the stakes in a looming battle over funding for the Department of Homeland Security, say Republican and Democratic officials.

Senate and House Republicans are warning against a standoff with President Obama and Senate Democrats that could shut down the department tasked with protecting the homeland within weeks of terrorist attacks against Western targets.

While Republicans are unified in their desire to reverse the executive order Obama issued after Election Day shielding an estimated 5 million illegal immigrants from deportation, some are warning Tea Party colleagues such as Sen. Ted Cruz (R-Texas) not to take the fight too far.