Washington is putting all options on the table in determining its response to Russia’s continued military build-up near Ukraine, a senior US official said on Friday. US Assistant Secretary of State for European Affairs Karen Donfried said the US is consulting with its European allies on the next moves in responding to Russia’s military escalation. “All options are on the table. And there's a toolkit that includes a whole range of options,” Ms Donfried said in a call with reporters. “What we're doing now is monitoring the region closely, consulting with our allies and partners on how do we deter Russian action.” Russia has amassed thousands of troops and artillery on the Ukrainian border in recent weeks, sparking US and European concerns of a possible invasion. US Secretary of State Antony Blinken is travelling to Latvia and Sweden next week to attend the Nato Foreign Ministerial and the Organisation for Security and Co-operation in Europe Ministerial Council. Russia’s military manoeuvres and threats to Ukraine will be high on both meetings’ agendas, the US official said. “The reason we take those kinds of unusual manoeuvres seriously is because we all remember what happened in 2014. We saw Russia illegally annex part of Ukraine's sovereign territory when it occupied Crimea. And since then, we have seen ongoing violence in eastern Ukraine,” Ms Donfried said. Asked if the US is willing to increase its military presence in Europe and in countries like Poland to deter Russia, the senior US official said the issue is being evaluated. “We will continue to revisit and evaluate how we are postured on the eastern borders [of Ukraine].” US Secretary of Defence Lloyd Austin hosted his Ukrainian counterpart Oleksii Reznikov last week at the Pentagon. “Our support for Ukraine's self-defence, sovereignty and territorial integrity is unwavering,” he said, without indicating the nature of that support or how the US would react if Russia invades Ukraine. <i>The New York Times</i> reported last week that US intelligence officials had warned their European allies that there is a short window of time to prevent Russia from taking military action in Ukraine. It quoted US and British officials as saying they are “increasingly convinced that President Vladimir Putin of Russia is considering military action to take control of a larger swath of Ukraine". The US is encouraging European countries to work together to develop a package of economic and military measures such as sanctions and military deployments to deter Moscow. In remembrance of Holomodor, the man-made famine in Ukraine orchestrated by the Soviet Union, President Joe Biden said on Wednesday that the US “reaffirms our commitment to the people of Ukraine today and our unwavering support for the sovereignty and territorial integrity of Ukraine". Also known as the Terror Famine, Holomodor resulted in the deaths of millions of Ukrainians in 1932 to 1933, when Joseph Stalin's government seized food, cut off aid and closed borders. Mr Putin on November 24 told European Council President Charles Michel that he was concerned by Ukraine's “provocations” to inflate tension in eastern Ukraine, the Kremlin said. The Russian president “expressed concern in connection with continuing provocations of the Ukrainian side aimed at exacerbating the situation on the line of contact".