"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", Esper said on Thursday.
He also praised the recent test of a ground-based intermediate-range missile and noted that it took less than nine months to develop the projectile from concept to launch.
Esper added that work on the missile began after the United States suspended its obligations under the Intermediate-Range Nuclear Forces (INF) Treaty in February 2019. He pointed out that it usually takes 24 months to plan and execute such a missile test.
A public affairs officer at Vandenberg Air Force Base said on Thursday that the United States has tested a land-based intermediate-range missile from the Vandenberg Air Force Base in the state of California.
The Defence Department said in a press release that the missile flew for more than 500 kilometres before it was terminated over the ocean. The data from the test flight will be used for the Defence Department's development of future intermediate-range capabilities, the release added.
The type of missile was banned under the INF Treaty.
On Sunday, the United States conducted a test of a ground-launched cruise missile to collect data for the development of future intermediate-range capabilities after the country withdrew from the INF Treaty. The Defence Department said in a release on Monday that the missile accurately hit its target after flying more than 500 kilometres.
On Tuesday, Russian Foreign Minister Sergey Lavrov said after meeting with US Secretary of State Mike Pompeo that Russia is ready to refrain from deploying intermediate-range missiles as long as the United States reciprocates.
The INF Treaty, signed by the United States and the then Soviet Union in 1987, was terminated on 2 August at the United States' initiative after it formally suspended its INF obligations six months earlier.
The United States and Russia have repeatedly accused each other of violating the agreement, which banned any ground-launched ballistic and cruise missiles with ranges of 500 to 5,500 kilometres (310 to 3,417 miles).