President Donald Trump's fight to tighten asylum laws faces an uphill battle in Congress, where Democrats are near certain to oppose the effort.

Trump on Saturday called off immigration raids which were set to begin as early as the following day but said that they would begin in two weeks unless lawmakers were able to "work out a solution to the Asylum and Loophole problems" at the border.

"Probably won't happen, but worth a try," Trump tweeted Sunday . "Two weeks and big Deportation begins!"

Chances are slim to none that Congress will pass sweeping immigration changes in the next two weeks – something Republicans were unable to do during the two years they held control of both chambers.

The House and Senate are both scheduled to vote on bills to provide some $4.5 billion in emergency funding for border operations and humanitarian aid. Though the House and Senate packages differ in how money should be allocated, neither address asylum laws or broad immigration reform.

And a bill introduced by Sen. Lindsey Graham, a Republican from South Carolina, that would restrict asylum is delayed in committee while Graham is reportedly seeking to craft a compromise immigration deal with Sen. Dick Durbin, a Democrat from Illinois.

Democrats have been steadfast in their opposition to tighter immigration laws. Late last year, they refused Trump's requests for border wall funding, resulting in a month-long government shutdown that ended only when Trump said he would declare a national emergency to pay for a border wall.

Trump and his allies have for months been pushing for changes to the country's asylum laws, which they say allow migrants to take advantage of the process to enter the U.S. and stay illegally. Under recent policy, thousands of asylum seekers are now being sent to Mexico to wait while their cases work through immigration court. Critics say the policy endangers many of those asylum seekers.

The Trump administration and congressional Republicans are particularly focused on the high pass rate of so-called credible fear interviews – preliminary interviews with detained asylum-seekers to determine if they have a legitimate reason to not be deported to their home countries while their asylum cases are processed. Trump's allies also say that a rule requiring immigration authorities to release family units seeking asylum relatively quickly has to lead to the exploitation of children and has encouraged migrants to arrive at the border as families.

In recent months, border authorities have apprehended record numbers of families at the border, many of whom are fleeing poverty and violence in Guatemala, Honduras and El Salvador and attempting to seek asylum in the U.S.

