A file picture dated 29 July 2013 shows an exterior view on the Harry S. Truman building, the headquarters of the US State Department, in Washington, DC, USA (reissued 18 August 2017). According to reports from 18 August 2017, technicians of the US Department of State arte working to fix a world-wide outage of its unclassified email system. EPA/MIKE THEILER

The United States on Wednesday rejected Russia’s demand to bar Ukraine from NATO and said it believed Moscow was ready to invade but offered what it called a new “diplomatic path” out of the crisis.

One month after Russia put forward sweeping security proposals, having sent tens of thousands of troops to Ukraine’s border, the United States delivered a reply in coordination with NATO allies and said it was ready for any eventuality.

Secretary of State Antony Blinken said he would speak again in the coming days to Russian Foreign Minister Sergei Lavrov, whom he met Friday in Geneva, amid a separate diplomatic initiative led by France.

“It sets out a serious diplomatic path forward should Russia choose it,” Blinken told reporters of the US response, which he said would remain confidential.

He renewed an offer on “reciprocal” measures to address mutual security concerns including reductions of missiles in Europe and transparency on military drills and Western aid to Ukraine.