Twitter's decision to mask five election-related tweets from President Trump on Saturday takes the total number of posts hidden on his widely followed account this week to nearly 20.

The tweets covered in the social media giant's latest applications of warning labels include one shortly before the 2020 race was called in favor of Democratic challenger Joe Biden, in which Trump says he won "by a lot" and others that allege sweeping voter fraud and illegal ballot-counting.

Twitter's warning, which tells users that "some or all of the content shared in this tweet is disputed and might be misleading," links to more information about the San Francisco-based company's civic integrity policy.

Twitter labels on Trump tweets (screenshot: FBN)

Along with the warning, Twitter significantly restricts engagement on such posts, the company has said. Users cannot like or comment on them, since the platform prohibits attempts to "manipulate or disrupt civic processes, including through the distribution of false or misleading information."

Twitter label on Trump tweets (screenshot: FBN)

The five freshly labeled tweets leave a total of 18 posts from the president that Twitter has labeled since Election Day, part of an effort among social media titans to prevent a repeat of 2016, when intelligence agencies say Russian operatives used disinformation to sway voters.

In the past week, Trump has repeatedly raised questions about vote-counting in battleground states such as Pennsylvania, Georgia, Nevada and Arizona, where he now lags behind Biden.

TWITTER MARKS 12 TRUMP TWEETS AS 'MISLEADING' IN 60 HOURS

A shift in positions as ballots were counted was widely predicted before Tuesday, however. Because some states didn't allow mail-in ballots -- which have tended to skew Democratic -- to be tallied in advance, their eventual tabulation eroded and, in some cases, overcame, Trump's leads on election night.

Those early totals had largely reflected in-person votes, many cast by Republicans who had heeded the president's statements that mailed ballots were ripe for fraud.

Among the Trump posts that Twitter applied warning labels to was a Friday statement that "tens of thousands of votes were illegally received after 8 p.m. on Tuesday, Election Day, totally and easily changing the results in Pennsylvania and certain other razor-thin states."

A county election worker scans mail-in ballots at a tabulating area at the Clark County Election Department, Thursday, Nov. 5, 2020, in Las Vegas. (AP Photo/John Locher)

Trump claimed in another that election observers were not allowed at Pennsylvania polling places, and said "BAD THINGS HAPPENED INSIDE."

TRUMP DECRIES LEAD THAT 'MIRACULOUSLY' DISAPPEARED

No evidence of widespread voter fraud has been discovered, though several misleading claims and videos alleging criminal activity involving ballot-counting have gone viral.

The Trump campaign has filed lawsuits in states including Pennsylvania, Georgia, Michigan and Nevada, alleging voter fraud and issues with ballot-acceptance deadlines. The campaign has fought to stop ballot counts until it is given "meaningful access" to observe them.

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The Associated Press contributed to this report.