Gitanas Nauseda was speaking as the Royal Danish Air Force sent four F-16 fighter jets and crew to Lithuania to help bolster patrols over the Baltic region as fears of war grow.

Asked if he agreed that continuing to talk to the Russians was pointless, the president said: "I don't agree.

"I think the time for diplomacy is still there.

"And we have to talk and we have to send very clear messages to some countries which are trying to increase attention in the region.

"And I think the time for diplomacy has not yet passed.

"It depends on us and especially it depends on our unity and very strong, firm signals NATO has to send. But NATO is able to send these messages and these signals."

When asked what he meant by this, he replied: "Signals which encourage the deterrence functions of NATO.

"I really believe in the deterrence effectiveness of NATO and we have to use it 100%. Collective strength and deterrence."

Fears have grown in Lithuania and other Baltic states over the last week as Russia continues its military build-up on Ukraine's border.

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But Lithuania's deputy minister of national defence told Sky News that the Russian military's move into Belarus - across his country's border- is "a game changer". The two countries are now carrying out joint exercises.

Margiris Abukevicius said: "Yes, I think most of us in Lithuania, but also in neighbouring countries, think that this is a game changer.

"We've been warning partners about this possibility for a number of years.

"We saw Belarusian military integration becoming a reality and it has really accelerated and this is a major threat."

Mr Abukevicius insisted the threat is no longer simply to Ukraine, adding: "When we see Russian troops in Belarus, it is an additional direct threat to Lithuania and countries in the region, but also for NATO because it means that we have Russian troops next to NATO borders and we cannot rule out any scenario."

Mr Abukevicius was aware that French President Emmanuel Macron spoke to Russia's President Vladimir Putin on Friday, but he was not optimistic the ongoing efforts at diplomacy will work.

He said: "I think if you compare the situation two months ago and now, I think the majority of us who were closely observing the developments and looking at what is happening in Belarus, we think this is a preparation for the real operation."

He welcomed the increased NATO air presence in his nation but said boots on the ground would send the strongest signal to Mr Putin.

The UK and US are said to be considering sending thousands more troops to bolster NATO's eastern flank but that extends far beyond the Baltic states.