Sen. Ted Cruz urged fellow Senate Republicans to use whatever congressional authority they have to push back at President Obama’s immigration reforms, including blocking presidential nominees and threatening to defund certain government programs or agencies.

While the Texas Republican stopped short of calling for an outright government shutdown to stop Obama’s executive action to allow more than 4 million illegal immigrants to legally remain in the United States, he called on Congress to “stand up and use the power of the purse to say … we will fund the operation of the federal government but we will not allocate taxpayer dollars to lawless and illegal amnesty.”