Discussions over the threat of a Russian military incursion and demands for an array of security concessions by the West will continue on Wednesday in Brussels at NATO headquarters, and on Thursday in Vienna at a meeting of the Organization for Security and Cooperation in Europe.

The highlight from the first round of deliberations Monday, however, was Ryabkov’s insistence that Russia was not preparing any imminent move against Ukraine, which it invaded in 2014 before annexing Crimea, and where it has backed an armed separatist uprising in the eastern region of Donbas that continues today.

We explained to our counterparts that there were no plans or intentions to attack, quote-unquote, Ukraine, Ryabkov told reporters. We dont have it, and we cant have it. There is no single reason to be afraid of any escalation, to be afraid of any escalatory scenario in this regard.

But on the subject of a potential NATO expansion, Ryabkov was uncompromising, requesting ironclad, waterproof, bulletproof, legally binding guarantees that Ukraine and Georgia will never ever become members of the military alliance.

This is one of the areas where we have the greatest difference of views with the U.S., Ryabkov said, adding of the Russian position: That would be a welcome change for the better in the position of NATO. We are fed up with the loose talk, half-promises, misinterpretations of what happened behind closed doors. We do not trust the other side.

In her own call with reporters, Deputy Secretary of State Wendy Sherman described a frank and forthright discussion with Ryabkov. The U.S. delegation arrived at the talks with a number of ideas [of] where our two countries could take reciprocal actions that would be in our security interest and improve strategic stability, Sherman said.

Specifically, the preliminary ideas raised by the United States included missile placements, Sherman said, and the U.S. delegation made clear that the United States is open to discussing the future of certain missile systems in Europe along the lines of the now-defunct [Intermediate-range Nuclear Forces] Treaty which former President Donald Trump withdrew the United States from in 2019.

We shared that we are also open to discussing ways we can set reciprocal limits on the size and scope of military exercises, and to improve transparency about those exercises, again, on a reciprocal basis, Sherman said.

POLITICO and other media outlets reported over the weekend that the United States was willing to discuss the placement of missiles in Ukraine and the scope of regional military exercises when the U.S. and Russian delegations met Monday in Geneva.

However, Sherman said the U.S. delegation was firm in pushing back on security proposals that are simply non-starters to the United States including Russias demand that the North Atlantic Treaty Organization formally bar Ukraine from entry into the military alliance.

We will not allow anyone to slam closed NATOs open door policy, which has always been central to the NATO alliance, Sherman said. We will not forgo bilateral cooperation with sovereign states that wish to work with the United States. And we will not make decisions about Ukraine without Ukraine, about Europe without Europe, or about NATO without NATO.

Alexander Ward contributed to this report.