Russian President Vladimir Putin said Thursday he offered to sell some of Russia’s newest weapons to U.S. President Donald Trump to prevent an arms race.

Putin said his country would produce hypersonic missiles, which had been banned under a Cold War nuclear pact that ended last month, but had no immediate plans to deploy them.

Putin told an economic forum in Vladivostok, Russia, he offered to sell the missiles to the United States during a phone call with U.S. President Donald Trump but Trump spurned the offer, saying the U.S. would produce its own, Reuters reported.

Putin said he feared an arms race that could extend to space.

Arms control tensions have grown since Washington pulled out of the Intermediate-Range Nuclear Forces Treaty last month, accusing Russia of violating the pact, despite Russian denials. U.S. national security policy long has been based on a combination of deterrence and arms control as a means of tempering the dangers of nuclear weapons and promoting a safer world. With the INF treaty gone, the U.S. and Russia are free to deploy any previously prohibited missiles, raising the prospect of an open-ended arms race.

The U.S. tested a cruise missile last month that would have been banned under the treaty. It hit a target 310 miles away.

“Of course, we will produce such missiles,” Putin told the forum but pledged not to deploy them unless the United States did so first. Russia is especially concerned about Pentagon plans to put the medium-range missiles in Japan and South Korea.

“This saddens us and is a cause for certain concern,” Putin said.

China also has expressed concern about last month’s test. U.S. Defense Secretary Mark Esper said the test actually was meant to curb China’s behavior.

“China is the greater challenge [than Russia] given its economic might, political weight, and its ambitions,” Esper said, adding China has studied U.S. military capabilities with an eye toward pushing the United States out of Asia.

“We want to make sure that we, as we need to, have the capability to deter Chinese bad behavior by having our own capability to strike at intermediate-ranges,” he said.

China never was a party to the INF treaty and has been developing intermediate range missiles for decades. One such missile is nicknamed the “Guam Express” because it is capable of taking out U.S. bases in the Pacific such as Andersen Air Force Base on Guam. The Dong-Feng 26 has a range of 1,864 to 3,400 miles.

The US has tested a missile previously banned under a now-defunct pact with Russia which limited the use of nuclear and conventional medium-range weapons The US has tested a missile previously banned under a now-defunct pact with Russia which limited the use of nuclear and conventional medium-range weapons Photo: DoD / Scott HOWE