MOSCOW, February 10. /TASS/. Washington's attempts to impose ultimatums on Moscow or offer supposed ‘big favors’ in exchange for unacceptable US demands are destined to fail in negotiations with Russia, Deputy Foreign Minister Sergey Ryabkov said at a press conference. "The use of ultimatums, manipulation, and efforts to convince us that we will be granted a big favor in exchange for agreeing to unreasonable demands - all this will not succeed in relations and talks with Russia," the senior diplomat emphasized. He recalled that the situation in the realm of international security and strategic stability has deteriorated "to a dangerously critical point" due to Washington's actions. "The dominant ambitions of the United States have manifested themselves, among other things, in the expansion into the post-Soviet space, in attempts to absorb Ukraine, which directly contradicts the repeatedly affirmed earlier core principle of indivisible security, to which the Western powers also agreed," the deputy foreign minister said. Not to mention the fundamental contradiction of such a policy with Russia's core interests, he added. Ryabkov reiterated the Russian side's consistent position: Moscow is prepared to discuss any issue, including the resolution of the Ukrainian conflict, only on an equal and mutually acceptable basis. At the same time, the senior diplomat stressed that Russia has previously mentioned "the window of opportunity for the normalization of Russian-US relations forming under the administration of [US President-elect Donald] Trump, at least a small window of opportunity." "Whether the United States will seize this opportunity depends solely and entirely on them," Ryabkov concluded.