A week after Russia's President Putin said he is ready to extend the New START nuclear arms reduction pact with the United States "without preconditions" by year's end, in an attempt to save it after the recent collapse of the Intermediate-Range Nuclear Forces (INF) treaty, the Pentagon has conducted another test of a previously banned ballistic missile.

Thursday's test-firing marks the second missile to be tested which would have fallen under the INF ban, which the Trump administration withdrew from earlier this year. The first test had taken place in August, during which time Putin said Russia will be forced to deploy banned missiles if the US does.

Screengrabs of the DoD footage of Thursday's launch, via The Drive.

Video footage of this week's test, like the one in August, was made public. The ground-launched missile reportedly few over the Pacific Ocean.

"The Department of Defense conducted a flight test of a conventionally-configured ground-launched ballistic missile at approximately 8:30 a.m. Pacific Time, today, Dec. 12, 2019, from Vandenberg Air Force Base, California," Pentagon spokesman Lt. Col. Robert Carver said.

Carver indicated the missile tested "terminated in the open ocean after more than 500 kilometers of flight. Data collected and lessons learned from this test will inform the Department of Defense's development of future intermediate-range capabilities." Crucially, the INF Treaty had specifically banned land-launched missiles with a range of 500 to 5,500 kilometers.

Today, @usairforce @30thSpaceWing & @DoDCTO Strategic Capabilities Office successfully tested a prototype conventional, ground-launched ballistic missile. Congrats to the joint gov’t-industry team for going from concept to launch in less than 9 months! pic.twitter.com/PiZw8xXDoY — Secretary of Defense Dr. Mark T. Esper (@EsperDoD) December 12, 2019

The other interesting element to the timing is that it came a mere two days after a rare visit by Russian Foreign Minister Sergei Lavrov to the White House, where arms control treaties were reportedly discussed with President Trump.

Few other details of the launch were given, per the AP:

The prototype missile was configured to be armed with a non-nuclear warhead. The Pentagon declined to disclose specifics beyond saying thew missile was launched from a "static launch stand" at Vandenberg Air Force Base in California and landed in the open ocean.

A statement by Defense Secretary Mark Esper has many worried the new tests and collapse of arms control treaties could trigger a new arms race with Russia.

Esper was asked at a briefing Thursday specifically about the possibility of placing US missiles in Europe, long a "worst-fear" scenario which the INF protected against. He responded:

"Once we develop intermediate-range missiles, and if my commanders require them, then we will work closely and consult closely with our allies in Europe, Asia, and elsewhere with regards to any possible deployments."

For Moscow's part, addressing a Russian defense meeting last week, Putin made an apparent appeal to the West, saying that he hopes to avoid a new arms race with the US and its allies, and vowed to in good faith refrain from deploying intermediate and shorter range missiles there where there are none.

"Russia is not interested in triggering an arms race or deploying missiles where there are none," Putin said. He also invited the US and European countries to join a Russian proposed moratorium on such new deployments and weapons. So far only France has greeted the proposal positively. Indicating the offer is conditional, he warned, "No reaction from other partners followed. This forces us to take measures to resist the aforesaid threats."