The UK will "not be deterred by bullying" by Russia when it comes to helping allies such as Ukraine, the Defence Secretary has said.
Ben Wallace told MPs he would visit "a number of countries" in eastern Europe and Scandinavia this week, "many of whom are very, very worried by what has been happening".
Talks are continuing over the Russian military build-up, with tens of thousands of troops massing near the border with Ukraine.
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It is hoped the crisis can be defused before it escalates into a full-blown military conflict.
Mr Wallace stressed that NATO is a "defensive alliance" as he criticised Russia for pushing a "false narrative" that it is "surrounding Ukraine when only one sixteenth of Russia’s border is bordered with a Nato member".
He told the Commons: "People seek to join Nato often as a result of other issues, and I think the question for the Kremlin is to ask themselves why so many countries sought that membership."
Mr Wallace went on: "The United Kingdom will work with whoever wants us to work with them who share our values.
"We will not be deterred by bullying, we will not be deterred by distance.
"We shall step up and help those countries in eastern Europe, those countries in Scandinavia and Ukraine, should they wish our assistance, as their right is, as a sovereign country; we respect their right as free sovereign countries and I ask other countries to do the same."
Mr Wallace also said it was important to have built up and helped Ukraine "sustain a navy capability".
He said: "We continue to provide support in many areas including security assistance and defence reform. Since 2015 the UK has helped build a resilience and capacity of the Ukrainian armed forces through Operation Orbital, which has trained over 22,000 Ukrainian troops."
Conservative Henry Smith (Crawley) asked for a update on the memorandum of implementation (MOI) between Ukraine and the UK to "build up naval capacity and naval bases".
Mr Wallace replied: "Yes it became very clear earlier on after about 2014 that Ukraine had lost large parts of its navy to the Russian illegal (occupation) of Crimea and it’s important to have built up and helped them sustain a navy capability.
"We have continued to invest in that and we also signed back last year, not only MOI, but an agreement to sell to the Ukrainian government navy patrol boats with weapon systems."