US Secretary of State Antony Blinken said on Wednesday that Washington had set out a “serious diplomatic path” to resolve the confrontation over Ukraine. The message came in the form of a letter to the Russian government that was delivered to Moscow earlier in the day. It serves as a formal response to a set of Russian demands in the <a href="https://www.thenationalnews.com/tags/ukraine/" target="_blank">Ukraine </a>crisis. “We make clear that there are core principles that we are committed to uphold and defend, including Ukraine's sovereignty and territorial integrity, and the right of states to choose their own security arrangements and alliances,” Mr Blinken said. He said the letter tells Russia that Kiev can choose its own allies, rebuffing Moscow's demand for a pledge that Ukraine will not join the Nato alliance. He also said he would speak to Russian Foreign Minister Sergey Lavrov in the coming days for Moscow's response to the US stance, which he described as a principled and pragmatic evaluation of concerns Russia has raised. “Our actions over the past week have sharpened the choice facing Russia now. We've laid out a diplomatic path we've lined up steep consequences should Russia choose further aggression”, Mr Blinken said. There was no immediate response from Russia but Russian officials have warned that Moscow would quickly take “retaliatory measures” if the US and its allies reject its demands. The document will not be released publicly to protect the confidentiality of the conversations, Mr Blinken said. He stressed that the US is prepared for a whole host of outcomes and that he hopes the US does not need to activate the roughly <a href="https://www.thenationalnews.com/world/us-news/2022/01/24/pentagon-puts-some-8500-us-troops-on-heightened-alert-status-in-ukraine-crisis/" target="_blank">8,500 troops currently on standby</a>. “There's no doubt in my mind that if Russia were to approach this seriously, and in a spirit of reciprocity, with the determination to enhance collective security for all of us, there are very positive things in this in this document that should be pursued,” Mr Blinken said. A series of security proposals by Russia have been rejected by Nato. Among those demands are a guarantee that Nato will never admit Ukraine as a member and that the military alliance will roll back deployments in other former Soviet bloc nations. While Washington has said that Russian demands for Nato to pull back troops and weapons from Eastern Europe and bar Ukraine from ever joining are non-starters, it says it is ready to discuss other topics such as arms control and confidence-building measures. Nato delivered a similar written response to Russia on Wednesday. Russian Deputy Foreign Minister Alexander Grushko told Interfax news agency, when asked how much time Russia would need to study Nato's response: "We will read it. Study it. The partners studied our project for almost a month and a half." While not a member of Nato or the EU, both organisations and member states have stood behind <a href="https://www.thenationalnews.com/world/uk-news/2022/01/26/kiev-mayor-vitali-klitschkos-nightmare-warning-for-ukraine/">Ukraine </a>and threatened Moscow with <a href="https://www.thenationalnews.com/world/europe/2022/01/26/ukraine-western-sanctions-choices-for-russia-and-vladimir-putin/">heavy economic sanctions</a> if an invasion takes place. Mr Blinken said the US and its European allies are facing the crisis with “unprecedented unity”, despite reports of German reluctance to send military aid to Ukraine. “I am absolutely confident in German solidarity in being with us and other allies and partners in confronting renewed Russian aggression against Ukraine,” Mr Blinken said.