Former President Barack Obama delivered his strongest criticism yet of Republican-led redistricting efforts on Thursday, telling Texas House Democrats in a private Zoom call that the state's proposed congressional map amounts to a "systematic assault on democracy." The remarks came as more than 50 Democratic lawmakers remain out of Texas in an effort to block a vote on a GOP plan that could secure as many as five additional Republican U.S. House seats ahead of next year's midterm elections.

The 30-minute call, first reported by ABC News and obtained by CNN, included former Attorney General Eric Holder, now chair of the National Democratic Redistricting Committee. Obama praised the Texas Democrats for their protest and pointed to California's move to launch its own redistricting in response. "What we all recognize is we can't let a systematic assault on democracy just happen and stand by," Obama told the group. "Because of your actions, because of your courage, what you've seen is California responding, other states looking at what they can do to offset this mid-decade gerrymandering that is highly irregular."

Obama said he initially preferred that congressional maps be drawn "in a non-biased way that an independent commission or some sort of neutral approach was taken so that Democrats and Republicans compete fairly." But he argued Republicans had "changed the calculus" by manipulating maps to "splinter Democratic voting blocs" and "pack in Democrats into one district so that they don't have influence in other districts."

Texas Democrats have been in Illinois for nearly two weeks to deny Republicans the quorum needed to pass the Trump-backed map during a special session called by Gov. Greg Abbott. They have signaled a willingness to return home if the session ends on Friday and California Democrats proceed with their own map, which Gov. Gavin Newsom formally launched Thursday.

State Rep. Ann Johnson told POLITICO that Obama "acknowledged what Texas is doing is wrong, and you have to be able to stand up in this moment." She added, "We should be brave enough to let the voters pick our lines and compete on fair ideas. And that's what he wants."

Texas House Democratic Caucus chair Gene Wu said the lawmakers were "especially excited" to have Obama address them, noting they have faced "bomb threats and lawsuits" since leaving. "Having President Obama speak with us and support us is proof that when Texas House Democrats stand up and fight back, we don't stand alone," Wu said in a statement to ABC News.

Obama also warned that the redistricting battle was part of a larger trend under President Donald Trump's administration, including "efforts at voter suppression, efforts at questioning the results of elections... militarization of cities, politicization of our justice departments and our military." He urged Democrats to see fair voting rights and fair maps as a benefit "for everybody, not just one side."

California's move drew a quick rebuttal from Sen. Ted Cruz (R., Texas), who said that if California eliminated its Republican districts, Texas should follow suit-potentially leaving the GOP with a net gain. Texas Republicans have filed legal action to compel the absent Democrats to return and threatened to remove them from office if they continue to boycott the vote.