Ukraine war: Why is Crimea so important to Russia and can Zelenskyy's troops recapture it?

As Ukrainian battlefield victories continue with the liberation of the city of Kherson, the spotlight once more falls upon the question of Crimea.

In the last few days, various Russian politicians have been discussing a possible attack on Kremlin positions on the key peninsula, Sky News reports.

They range from Viktor Bondarev saying that Ukraine has "neither the resources nor the military potential" to retake Crimea, to Russian MP Andrei Gurulyov urging Moscow to calculate the possibility of a Ukrainian attack supported by NATO.

Fellow Russian MP Mikhail Sheremet warned that Ukrainian troops will experience a "final crushing blow" if they launch a major offensive on Crimea.

Once the jewel of the Russian Empire, the strategically important territory on the Black Sea has a long history, including holding out against the Nazis in the Second World War and more recently its annexation by Vladimir Putin in 2014.

When Russia launched its full-scale invasion of Ukraine in February, President Volodymyr Zelenskyy was at first cautious when it came to publicly voicing his ambitions about the coastal territory.

But as the war has gone on and Ukrainian troops have secured a more and more battlefield victory, he has been clearer: Crimea is Ukraine, and his armed forces will retake it.

Ukrainian deputy defence minister Volodymyr Havrylov told Sky News that Ukrainian forces could be back in Crimea by the end of December - and the entire war with Russia will be over by the spring.

He said the recapture of Crimea was "only a matter of time", saying this could be helped by what is known as a "black swan" event - something unpredictable - happening in Russia, such as the sudden collapse of the Putin regime.

There was "also a military option as well with some kind of combination of forces, resources, and something else".

"We can step in Crimea, for example, by the end of December. Possible, possible. Not excluded that it be so," he added.

What are the chances of Ukraine retaking Crimea by force?

Crimea is a huge part of Russia's history and Russia never believed that Crimea was not Russian, retired air-vice marshal Sean Bell told Sky News.

Not only that, but defensive positions left over from the Second World War - when the territory held out against Nazi forces - make it a very difficult military objective, he said.

"Those defensive positions still remain in place today," he said.

"So the prospect from most military perspectives, including the US, the most senior US defence authority, have said that the chances of Ukraine ever militarily taking back Crimea are very, very small."