The U.S. will “aggressively” enforce severe sanctions against Russia that President Joe Biden will announce on Thursday in response to the nation’s invasion of Ukraine, an administration official said.

U.S. officials been working with counterparts in Europe in recent weeks to prepare the measures, Matthew S. Axelrod, assistant secretary for export enforcement at the U.S. Department of Commerce’s Bureau of Industry and Security, said on Thursday. The U.S. is prepared to implement export-control measures in coordination with a large number of allies and partners, a senior administration official said earlier this week.

“I don’t want to get ahead of the president’s announcement later today, but he’s made very clear that there will be severe sanctions,” Axelrod said in a virtual event hosted by Silverado Policy Accelerator. “I’ll make very clear here—not that there should have been any doubt—that we will enforce the severe sanctions aggressively.”

Within BIS, Axelrod leads a group of special agents and analysts dedicated to the enforcement of U.S. export-control laws. The team is responsible for stopping exports of sensitive goods and technologies that can be used for malign purposes, such a weapons of mass destruction proliferation, military and military-intelligence pursuits.

Biden on Wednesday night announced he would impose “further consequences” on Russia after Vladimir Putin ordered troops into eastern Ukraine, which the U.S. leader condemned as an “unprovoked and unjustified attack.”

Biden said he would outline the punishments in an address to the American people on Thursday, after discussing the unfolding crisis with other Group of Seven leaders in the morning. Biden is scheduled to speak at 12:30 p.m. in Washington.

Administration officials on Wednesday night were still deciding what the next round of penalties would look like, according to a White House official.

Earlier Wednesday, the White House sanctioned the builder of the Nord Stream 2 gas pipeline and its corporate leadership. That came on top of a sanctions package announced Tuesday following Putin’s recognition of breakaway territories in the Donbas region of eastern Ukraine as independent states.

Apart from his comments on Russia, Axelrod, who was confirmed by the Senate in December, announced that the BIS is going through two reviews of its policies.

In one review, BIS is evaluating ways to strengthen administrative enforcement—cases that aren’t prosecuted under criminal procedures but can result in fines or the denial of export privileges.

That review includes how often the bureau uses “no admit, no deny” resolutions instead of requiring companies to admit to a statement of fact in a case; whether penalty amounts are properly calibrated to reflect national security harm or are in some cases understating it; and when to pursue administrative cases alongside criminal cases, Axelrod said.

In the second review, the bureau is looking at how its voluntary self disclosure programs work, and how to concentrate resources on cases that may warrant a follow-up and administrative or criminal penalties, he said.

“The way things have operated in the past aren’t necessarily the way they’re going to operate going forward,” Axelrod said.