Russian President Vladimir Putin said on Thursday that the threat of nuclear war should not be underestimated, but that he hoped that common sense would prevail.

Speaking at his annual news conference, Putin said it was hard to predict what the consequences would be of a U.S. withdrawal from the landmark Intermediate-range Nuclear Forces Treaty, signed in 1987.

"It's a real shame that there's a tendency to underestimate them (nuclear weapons). It is a legitimate issue, and it is even growing," Putin said.

"They (the US) left the (Intermediate-range Nuclear Forces) Treaty, what will come of that? It is difficult to imagine how the situation will develop from there. If these rockets appear in Europe, what do we do? Of course, we will need to provide our own security. Let them not say afterwards that we were trying to achieve some sort of advantage. We are not aiming for an advantage, we are aiming to retain balance and to provide for our own safety," the Russian premier continued.

Crimea

When asked about the country's ongoing detention of Ukrainian sailors following last month's altercation in the Kerch Strait, Putin once again put the blame squarely on Ukrainian authorities.

"What happened in November is clearly a provocation by Ukraine," the Russian leader said, adding: "Bottom line is: one needs to respect navigation rules" in the Strait.

He also disputed the annexation of the Crimean peninsula, arguing it "was attached to Russia following a people's vote in a referendum there."

READ: 'Euronews isn't chirping on this': Putin hits out over Russian sailors

Putin also blamed Ukraine and western authorities for implementing sanctions which "have been imposed not only on the authorities of the Crimean Republic and Sevastopol (Crimea's largest city) but on everyone."

Finally, he boasted that the country "invests heavily in the development of the civil infrastructure in Crimea" and said 300 billion roubles (€3.8 billion) will be poured in the region next year.

"Therefore, the defence of this (investment) is a priority," he warned.

'Russophobia'

Putin also hit out at the West for its "russophobic approach" which he said is designed to "contain the development of Russia as a possible rival."

He alluded to a different set of rules being applied to his country, using the recent murder of Saudi columnist Jamal Khashoggi and the nerve agent attack on former Russian spy Sergei Skripal as a comparison.

"Khashoggi was killed this is clear, everybody has recognised it," he said.

"Meanwhile, Skripal is alive, thank God. Nevertheless, Russia has been hit by a host of sanctions, while nothing happens with regard to that case (Khashoggi's) — absolute silence," he added.

Relations with Britain

Putin describes Russia's relationship with the UK as "gridlocked" since the March attack in Salisbury which Britain has blamed on Russia — allegations Russia firmly denies.

Commenting on Brexit, he said he hoped "common sense prevails," declaring himself against a second referendum on the issue.

He added that his country's economy will, "to the smallest degree," be impacted by Britain's exit from the EU and said Russia is "interested in the reconstruction of full-scale relations with the UK."

"As much as, I suppose, Britain is interested, and primarily the business community in the country," he said.

I'll probably get married 'one day'

It wasn't all heavy politics today. Some much lighter questions were also asked during the marathon press conference with journalists looking to get a glimpse into the personal life of the notoriously private leader.

One particularly bold reporter asked Putin if he was married and enquired as to "who the chosen one" might be.

Read about his response here.