Ukrainian president Volodymyr Zelenskyy will meet with UK prime minister Rishi Sunak on Monday.

It was announced last week that Britain will supply the besieged eastern European nation with long-range Storm Shadow missiles.

The missiles carry a 450kg warhead to a range of up to 350 miles (560km), but defence secretary Ben Wallace said he had received assurances they would not be used to hit targets within Russian territory.

Mr Zelenskyy appeared to reference the gifting of those weapons as he announced on Monday morning that he'd be visiting Downing Street.

He wrote on Twitter: "Today – London. The UK is a leader when it comes to expanding our capabilities on the ground and in the air. This cooperation will continue today. I will meet my friend Rishi.

"We will conduct substantive negotiations face-to-face and in delegations."

The Prime Minister said: “This is a crucial moment in Ukraine’s resistance to a terrible war of aggression they did not choose or provoke.

“They need the sustained support of the international community to defend against the barrage of unrelenting and indiscriminate attacks that have been their daily reality for over a year. 

“We must not let them down.

“The frontlines of Putin’s war of aggression may be in Ukraine but the fault lines stretch all over the world. It is in all our interest to ensure Ukraine succeeds and (Vladimir) Putin’s barbarism is not rewarded.

“That is why the UK is sustaining our support to Ukraine – from tanks to training, ammunition to armoured vehicles. And this message of solidarity will ring loud in all my meetings with fellow world leaders in the days ahead.”

Mr Zelenskyy will also attend the next meeting of NATO in person, with Ukraine pushing to join the alliance following the Russian invasion.

Formerly a nuclear state following the collapse of the Soviet Union, Ukraine agreed to give up its nuclear weapons in return for the U.S, the UK and Russia agreeing not to threaten or use economic or military force against it.

Read More: UK to supply Ukraine with long-range missiles in war with Russia

Kyiv had asked for a "security guarantee" to be included in that agreement, signed in Budapest, which would have acted much like NATO's article 5.

However, the three nations agreed only to "security assurances", namely that they would all respect Ukraine's territorial integrity, rather than pledging military intervention if the country was invaded.

The country is now hoping to join NATO following the invasion by Russian forces in 2022.