Joussen tackled the issue head-on in a letter to Tui staff on Monday (28 February), in which he acknowledged Mordashov’s approximately one-third stake in the group, reported to be around 34%.

"Some of you have asked me about our largest single shareholder Alexey Mordashov and our position with him," said Joussen. "Mr Mordashov has been a Tui shareholder for around 15 years and has held about a third of our company since he propped it up during the Covid crisis."

The UK, the EU and the US have all placed stringent financial sanctions on Russia in recent days following its invasion of Ukraine on Thursday (24 February), with a particular focus on freezing Russian financial assets. The country could also be barred from the Swift international banking payment system, which would make it harder to quickly move money in and out of Russia.

Joussen, though, made clear he did not anticipate any "last negative consequences" for Tui should Mordashov be affected. "Two thirds of our shareholders are from Germany, the EU, the UK, the US, or are funds," said Joussen. "Mr Mordashov is also one of 20 representatives on the [Tui] supervisory board elected by shareholders at the annual general meeting.

"However, our company is run by the executive board, like any German public limited company, and not by the shareholders or the supervisory board. We therefore assume any restrictions or sanctions against Mr Mordashov will not have any lasting negative consequences for us as a company."

Joussen added it would be some time yet before a full picture of how relations between Russia and the EU will develop, "and how economic cooperation between Russia and the west will develop in the future".

Elsewhere, Joussen said Russia’s invasion of Ukraine and the fighting over the weekend had left him "stunned", adding he could "hardly imagine the suffering" of the Ukrainian men and women fighting to defend their country, and the families fleeing their homeland.

"A war of aggression in the middle of Europe, an attack on a sovereign country, on innocent Europeans – all this was hardly imaginable after the Cold War and in the era of dialogue and cooperation," he said. [And] although it gives us hope that the free world is showing unity, worries about further developments now predominate."

Joussen said that while the impact of the invasion on Tui’s business was "certainly not the first priority", the group was monitoring the situation "intensively" and assessing the potential consequences. "In order to ensure the safety of our customers, we will make or have already made adjustments in some areas, such as flight routes and cruise destinations," he said.

"We are in contact with the employees of service providers in Ukraine who work for us and are supporting them as best we can to keep themselves and their families safe. Tui Cruises is also intensively looking after crew members from Ukraine who are employed on board our fleet of ships.

"One thing is clear: we will be true to our values and show our position. Like hardly any other sector, tourism stands for international understanding and peaceful exchange across borders and cultures – we feel particularly committed to this. Let’s all hope that humanity and reason will prevail and peace will return to Europe."