President Donald Trump said that if Democrats “want to play tough” when they control the House of Representatives next year, he will declassify documents that will be “devastating” to them.

“If they want to play tough, I will do it,” Trump told the New York Post in an interview Wednesday. “They will see how devastating those pages are.”

Democrats are poised to launch a series of investigations after winning a majority in the House in November. Democratic-controlled committees are likely to probe a range of issues including Russian interference in the 2016 presidential election, Michael Cohen’s payments to women who say they’ve had affairs with Trump (allegations he denies), potential obstruction of justice and Trump’s finances.

The President told the Post he wants to save the documents for when he can use them against the Democrats most effectively. “It’s much more powerful if I do it then,” Trump told the Post, “because if we had done it already, it would already be yesterday’s news.”

It’s not clear what documents he is referring to.

It’s an escalation of what Trump told reporters on November 7 after Democrats had retaken control of the House during the midterm elections.

During that post-midterm news conference, Trump said that if Democrats start investigating his administration then he would be moving to “a warlike posture.”

When asked by a reporter if he would show Democrats that he could could “play that game and investigate” Democrats, Trump said, “Oh, yeah. Better than them.”

While it’s uncommon for most presidents to use, or threaten to use, declassification as a political tool, Trump has done so on multiple occasions in 2018.

In September, Trump also threatened to declassify various documents and text messages related to the Russia investigation, but then appeared to back off the unprecedented move.

The President initially directed the Justice Department and the Office of the Director of National Intelligence to initiate the “immediate declassification” of selective portions of the Foreign Intelligence Surveillance Act application on former Trump foreign policy aide Carter Page, according to a statement from White House press secretary Sarah Sanders. His request broadly included “all FBI reports of interviews” prepared in connection with the FISA applications, which are usually closely guarded by the FBI.

But Trump then sent two tweets stating that the Justice Department inspector general had been asked to review the documents “on an expedited basis.” The President added, “In the end I can always declassify if it proves necessary.”