Facebook's ban on political ads will end on Election Day, a company spokesperson confirmed — meaning that both parties could resume slinging their paid political messages just as litigation and PR battles are ramping up over protracted counts and recounts.

Less than a year ago, Zuckerberg dismissed the idea of such a ban, saying in a speech at Georgetown that "banning political ads favors incumbents and whoever the media chooses to cover.” But critics have pressed the company to take stronger action against misinformation and voter suppression, particularly as more states turn to wider use of mail-in voting and because of the likelihood that the final results could be delayed for days or weeks beyond Nov. 3.

"This election is not going to be business as usual," Zuckerberg wrote in a post Thursday. The ban will apply to new political and issue-based ads, although existing ads will be allowed to continue to run.

The announcement quickly attracted ire across the political spectrum.

Samantha Zager, the Trump campaign's deputy national press secretary, accused Facebook of trying to hobble the president's reelection bid, saying that if Democracts were to "drop another fake Russian disinformation dossier," the campaign would be unable to counter subsequent media coverage.

"When millions of voters will be making their decisions, the President will be silenced by the Silicon Valley Mafia, who will at the same time allow corporate media to run their biased ads to swing voters in key states," Zager said.

"We know Big Tech hates Donald Trump, we know some of their employees have engaged in the leftist riots staged by Joe Biden’s supporters, and now we know they are silencing the President at the most important time of all," she continued.

Liberal groups including ACRONYM and Media Matters for America also condemned Facebook's decision, saying it would benefit Trump and his right-wing supporters who have amassed a large following on the social network. The Biden campaign did not immediately respond to a request for comment.

Media Matters President Angelo Caruso said ads are "at the bottom of the list" as far as disinformation concerns on Facebook, and that the company has still failed to adequately address posts from right-wing extremists and others spreading hateful or manipulative messages.

“Facebook’s new ad policy announcement is designed to fool the media and the public into thinking the company is taking disinformation seriously," Caruso said, adding that "this new policy is pointless — and may even do more harm than good."

Tara McGowan, CEO of left-leaning ACRONYM, called Zuckerberg's announcement a "shallow and dangerous public relations move" that will benefit conservative publishers on Facebook whose posts are considered news rather than political speech. Without ads, political groups and campaigns will have fewer ways to respond.

"When the ability to run new ads are taken off the table, the only pages that can reach and influence Americans at any meaningful scale are those with the largest organic followings on the platform. Who are those pages? Fox News, Breitbart, Ben Shapiro, to name just a few," she said in a statement.

The Trump and Biden campaigns have shelled out tens of millions of dollars to advertise on Facebook's network, which has the broadest reach of any social media platform in the U.S. The campaigns also heavily advertise on television, Google-owned YouTube and through the mail, methods that will still remain viable until Election Day.

The ban is a departure for Facebook and for Zuckerberg, who has generally opposed restricting political speech and pointedly refused a year ago to go along with Twitter's ban on all political ads. He has argued in the past that the company should not be the arbiter of truth or determine what kind of political speech users can share and see.

"It's important that campaigns can run get out the vote campaigns, and I generally believe the best antidote to bad speech is more speech, but in the final days of an election there may not be enough time to contest new claims," Zuckerberg wrote Thursday.

The company will also expand its efforts to crack down on voter suppression efforts, removing posts that not only explicitly spread lies about voting but also those that imply falsehoods as well. Facebook previously announced a partnership with state election officials to remove voting misinformation in the days before the election, but the company will begin those efforts Thursday instead.

And Facebook will limit the number of people whom users can forward messages to through Facebook Messenger in a bid to halt misinformation from going viral.

Zuckerberg cautioned that a "very heated period" could follow the election as ballots are being counted and accusations of misconduct are leveled in an effort to undermine the outcome. "It's important that we prepare for this possibility in advance and understand that there could be a period of intense claims and counter-claims as the final results are counted," he said.

The Voter Information Center that Facebook debuted last month as a one-stop location for election-related information will contain results and inform people that delays are to be expected, he said. Facebook will also append informational labels to posts that question the legitimacy of the election or certain voting methods, as the company has already begun doing on posts that mention voting.

Facebook has revealed efforts to thwart election-related misinformation in dribs and drabs in recent years, but the policy changes outlined Thursday are expected to be the last before the Nov. 3 election, Zuckerberg said.

"We'll enforce the policies I outlined above as well as all our existing policies around voter suppression and voting misinformation, but to ensure there are clear and consistent rules, we are not planning to make further changes to our election-related policies between now and the official declaration of the result, Zuckerberg wrote.