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A ban on Russian planes flying over and landing in the UK was extended on Friday to include private jets.
Transport Secretary Grant Shapp said he has strengthened the flight ban with immediate effect.
“[Russian President Vladimir] Putin's actions are unlawful and anyone benefiting from Russia's aggression in Ukraine is not welcome here,” he said.
“I've strengthened our ban in the UK so that no Russian private jet can fly in UK airspace, or touchdown — effective immediately.”
Russia imposed its own retaliatory ban on UK flights from landing in and flying over the country.
Russia’s civil aviation authority, Rosaviatsiya, said that all flights operated by UK airlines to Russia as well as transit flights will be banned from Friday.
It said the measure was taken in response to the “unfriendly decisions” by the British authorities who banned flights to the UK by Russia's national airline Aeroflot as part of sanctions over Moscow’s invasion of Ukraine.
“A restriction was introduced on the use of Russian airspace for flights of aircraft owned, leased or operated by an organisation linked to or registered in the UK,” the Russian aviation authority said.
The UK will “imminently” level personal sanctions against Mr Putin and Foreign Minister Sergey Lavrov, UK Prime Minister Boris Johnson announced on Friday.
On Thursday, he outlined a package of sanctions against Russia, days after imposing a first set of measures.
The latest sanctions are aimed at Russian elites, companies and financial institutions. Russian bank assets in the UK have been frozen, shutting off the country’s banking system from UK financial markets.
All Russian state-owned firms have been banned from raising finance on British markets.
More than 100 oligarchs and companies in Mr Putin’s inner circle have also been sanctioned.
The prime minister said the latest sanctions include “all the major manufacturers that support Putin’s war machine".
After Ukrainian President Volodymyr Zelenskyy spoke to Mr Johnson on the phone on Friday morning, he said Ukraine “needs the support of partners more than ever".
“We demand effective counteraction to the Russian Federation. Sanctions must be further strengthened,” Mr Zelenskyy added.
Mr Johnson assured Mr Zelenskyy that “the world is united in its horror at what Putin is doing” and praised the “bravery and heroism of the Ukrainian people”, Number 10 said.
“The Prime Minister committed to provide further UK support to Ukraine in the coming days as the people of Ukraine and the world continue to demonstrate that Putin cannot act with impunity,” a statement added.
The British government is expected to announce further details, including names of companies and people who will be sanctioned as a result of the invasion, next week.
The measures will prohibit Russian companies from raising finance on UK markets, where in recent years they have been able to raise tens of billions.
There will also be a package of sanctions against Russian propaganda broadcasters whose programmes are aired in Britain, which is expected to include Russia Today.