The United States and Russia on Wednesday held their first bilateral Strategic Stability Dialogue which the leaders of the two nuclear superpowers agreed to launch last month toward future arms control initiatives.

The discussions in Geneva between senior officials of the two countries were "professional and substantive," the State Department said in a press release. The two sides agreed to meet again in a plenary session at the end of September, while holding informal consultations in the interim, it said.

Russian President Vladimir Putin (L) greets U.S. President Joe Biden during their summit on June 16, 2021 in Geneva. (Getty/Kyodo)

The U.S. delegation, led by Deputy Secretary of State Wendy Sherman, spoke about policy priorities, the current security environment and the prospects for new nuclear arms control, among other issues, according to the department.

The Russian side was represented by Deputy Foreign Minister Sergey Ryabkov.

The administration of U.S. President Joe Biden is seeking to build a more "stable and predictable" relationship with Moscow as Washington steps up its efforts to counter China's growing assertiveness.

In February, the United States and Russia agreed on a five-year extension of the last remaining treaty capping their nuclear arsenals -- the New Strategic Arms Reduction Treaty.

The New START limits each side to no more than 1,550 deployed nuclear warheads and no more than 800 deployed and non-deployed intercontinental ballistic missile launchers, submarine-launched ballistic missile launchers and heavy bombers equipped for nuclear armament.

But the treaty does not restrict the number of tactical nuclear arms. The United States has been concerned that Russia's buildup of its inventory of such weapons could pose a threat to members of the North Atlantic Treaty Organization.

Washington is looking at "arms control that addresses all Russian nuclear weapons," The Wall Street Journal said, citing remarks by a senior State Department official.

Russia, meanwhile, has been wary of U.S. missile defenses.

"We remain committed, even in times of tension, to ensuring predictability and reducing the risk of armed conflict and threat of nuclear war," the State Department said in the press release.

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