Russia demanded Friday that the United States and its allies halt all military activity in Eastern Europe and Central Asia in a sweeping proposal that would establish a Cold War-like security arrangement, posing a challenge to diplomatic efforts to defuse Russia's growing military threat to Ukraine.

The Russian proposal — immediately dismissed by NATO officials — came in the form of a draft treaty suggesting NATO should offer written guarantees that it would not expand farther east toward Russia and halt all military activities in the former Soviet republics, a vast swath of now-independent states extending from Eastern Europe to Central Asia.

The proposals codified a series of demands floated in various forms in recent weeks by Russian officials, including by President Vladimir Putin in a video call with President Joe Biden. They represent in startling clarity goals long sought by Putin, who analysts say is growing increasingly concerned that Ukraine is drifting irretrievably into a Western orbit, posing a grave threat to Russian security.