It would take only a matter of months for the Department of Energy to perform an underground nuclear-explosive test with minimal diagnostics, a Pentagon official said Tuesday.

Previous heads of the agency’s semiautonomous National Nuclear Security Administration (NNSA) have talked “about a very quick test with limited diagnostics, though certainly diagnostics, within months,” said Drew Walter, who is performing the duties of deputy assistant secretary of defense for nuclear matters. “A fuller test, fully diagnostic, and lots of data, all the bells and whistles, so to speak, might be measured in years. But ultimately, if the President directed because of a technical issue or a geopolitical issue, a system to go test, I think it would happen relatively rapidly.”

Walter also said that he believes the NNSA has a borehole at the Nevada National Security Site that would be suitable for such a rapid test.

Walter spoke to members of the press on a webcast hosted by the Washington-based nonprofits the Mitchell Institute and the Advanced Nuclear Weapons Alliance. It was one of the first Washington media events focused on nuclear weapons since the Washington Post on Friday reported that the Trump administration discussed a possible nuclear-explosive test in a May 15 meeting.

NNSA headquarters in Washington did not immediately reply to a request for comment on Tuesday.

The U.S. has observed a nuclear test moratorium since 1992, relying instead on subcritical plutonium experiments to verify that American nuclear weapons retain their designed destructive potency as they age. Some of these experiments are performed at the Nevada National Security Site, which is in the middle of upgrading its underground U1a Complex to continue, and enhance, the subcritical regime into the latter half of this century.

Separately, Walter said the Pentagon continues its analysis of alternatives for a possible future nuclear-armed Sea Launched Cruise Missile. The “initial results” of that “ongoing” analysis, in which the Pentagon will broadly outline what it wants the missile to look like, should be finished “shortly,” Walter said.

The early results will feed into “discussions this fall” about how the proposed sea-launched nuke might fit into the Pentagon’s fiscal year 2022 budget request, Walter said. The budget request is notionally due in February 2021.

Meanwhile, Walter said the ongoing COVID-19 pandemic appears not to have delayed any major NNSA programs, just yet.

“At this time I’m not seeing any indication there’s going to huge slowdowns on the warhead side,” Walter said. “[S]mall perturbations are certainly possible.”