After President Donald Trump insisted on Wednesday that he still intends to deliver the State of the Union address next week even though Democratic House Speaker Nancy Pelosi (Calif.) rescinded his invitation last week, the speaker quickly doubled down on her decision.

"I am writing to inform you that the House of Representatives will not consider a concurrent resolution authorizing the president's State of the Union address in the House Chamber until government has opened," Pelosi wrote to Trump, adding that she'll welcome him for the speech after the shutdown ends.

Pelosi was responding to a letter that Trump sent to her earlier Wednesday, in which the president said he'd confirmed with the Department of Homeland Security (DHS) and the United States Secret Service that despite the ongoing shutdown—the longest is U.S. history—"there would be absolutely no problem regarding security with respect to the event."

Last week, Pelosi rescinded her invitation for Trump to deliver his address on Jan. 29, citing security concerns in light of the shutdown, which was prompted by the president's demands for billions of dollars to build a wall along the U.S.-Mexico border. Trump responded with a "childish" letter canceling her congressional delegation trip to Brussels, Egypt, and Afghanistan.

Asked by reporters about Pelosi's latest letter on Wednesday, Trump said he was "not surprised."