Former German Chancellor Gerhard Schröder, who describes himself as a personal friend of Russian President Vladimir Putin, called on Thursday for an early end to the war in Ukraine and for Europe's remaining ties with Russia not to be severed, Reuters reported.

"There have been many mistakes - on both sides. But Russia's security interests do not justify the use of military means either," Schröder

wrote in a post on LinkedIn.

"With the necessary sanctions, care must be taken not to completely cut the remaining political, economic and civil society ties that exist between Europe and Russia," he added.

Schröder chairs the shareholder committee of Nord Stream 2, the company responsible for building the controversial Russian gas pipeline to Europe, which is now under US sanctions, although he is not personally affected by the sanctions, the news agency noted.

On Thursday morning, Russian President Vladimir Putin announced the launch of a military operation in Ukraine.

He said that Moscow did not intend to occupy Ukrainian territories. According to the Russian president, the goal is to demilitarize and denationalize Ukraine.

Later, the Russian Defence Ministry informed about missile strikes against the Ukrainian military infrastructure. In particular, it spoke about spot strikes on airfields and command posts near Kyiv, Kharkiv and Odessa.

Ukrainian President Volodymyr Zelenskyy imposed martial law. He said he would break off diplomatic relations with Russia.

Ukraine has also closed its airspace.