Watch: First White House press briefing since Parkland shooting, Mueller indictments

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White House press secretary Sarah Sanders is scheduled to field reporters' questions for the first time in a week on Tuesday.

Sanders will likely be asked about last week's school shooting in Florida, special counsel Robert Mueller's indictments of Russian election meddlers and the aftermath of recent failures to pass immigration legislation — all of which occurred after the previous press briefing.

Sanders may have been away from her podium, but President Donald Trump has been busy responding to each of these events and more, chronicled in part by a 20-tweet tirade over the weekend.

On Saturday, Trump suggested that the expenditure of FBI resources in the Russia probe was connected to the Bureau's failure to prevent the shooting.

After the special counsel announced indictments of 13 Russian individuals and three entities on Friday — in part for conducting a campaign of "information warfare against the United States of America" to influence the 2016 election — Trump claimed in a tweet to have "never said Russia did not meddle in the election." In fact, the president has previously cast doubt on not only the probe into potential collusion between the Trump campaign and Russia, but on Russian election meddling in general.

Also on Friday, Mueller's team charged the son-in-law of a Russian oligarch with lying to federal authorities about communications with Richard Gates, a former Trump campaign official and close associate of onetime campaign chief Paul Manafort.

Trump's tweet storm continued on Tuesday, when the president claimed one of the 19 women accusing him of sexual misconduct had made up a story published that morning in the Washington Post.

But while the deluge of new headlines may draw significant attention at the briefing, questions remain about the White House's handling of security clearances in the wake of recent allegations against former White House official Rob Porter.

Porter, Trump's former staff secretary, assisted Chief of Staff John Kelly in overseeing the flow of documents that passed the president's desk. Porter had access to classified materials under a temporary "interim security clearance" during and after the FBI's background check.

Sanders said last Tuesday that the FBI sent a completed background report to the White House in November. But she said the White House personnel security office was still in the midst of its own investigation into Porter by the time the British tabloid Daily Mail published interviews with Porter's ex-wives alleging physical and verbal abuse in February.

That explanation contradicted Sanders' statement a day earlier when she said the security clearance process "doesn't operate within the White House."

In Senate testimony Tuesday, FBI Director Christopher Wray said the Bureau had issued a partial report on Porter last March and completed its background check in late July.

The briefing scheduled for Wednesday was canceled in light of a shooting at a Parkland, Florida high school, in which a rifle-wielding gunman killed 17 students and adults. The White House schedule did not include a press briefing the following day.