Former Gov. Jeb Bush (R-Fla.) took a tougher line on illegal immigration Thursday, writing in an op-ed that federal law should be changed so that people who illegally cross the border aren't released from custody as they await hearings.

Bush, who has expressed support for immigration reform and is considered a White House contender in 2016, said the existing law allows people who don't actually deserve asylum in the United States to too easily take cover under protections for real asylum seekers.

“We must close loopholes that allow for individuals to be released from federal custody between hearings," Bush wrote in the op-ed in The Wall Street Journal with Clint Bolick, director of the Goldwater Institute’s Scharf-Norton Center for Constitutional Litigation in Phoenix. 

"Except for those deserving few who may demonstrate true cause for asylum or protection from sex trafficking, these children must be returned to their homes in Central America,” Bush wrote.

Border authorities are dealing with a flood of Central American children seeking to cross the border, and apparently believing they will be allowed to stay.

Congressional Republicans have called for changing a 2008 human trafficking law so that authorities could more quickly turn people back to their home countries. The administration also supports changing the law, but most Democrats in Congress oppose doing so.

Bush suggested few children would be deported if the U.S. government doesn’t change its laws.

“Despite President Obama's reassurances, few of these children are likely to return home if nothing changes,” Bush said.

Bush blamed both Obama and Congress for the border crisis. He argued the core problem is not new but has been exacerbated by a number of factors. 

He also said the administration and Congress should work together to write a new immigration law to deal with underlying problems.

“President Obama has promised to once again act unilaterally if Congress fails to take up immigration reform. Now is the time for House Republicans to demonstrate leadership on this issue. Congress should not use the present crisis as an excuse to defer comprehensive immigration reform,” he said.

Earlier this year, Bush received some criticism from Republicans after he described illegal immigration as an “act of love.”