Hansen suffered a stroke on March 15.

"I am so grateful to you all for your messages of support and I need them all", the Norwegian wrote on Twitter.

The last four weeks have been "very tough", Hanen said, but that he was "fighting everyday to regain my strength".

Hansen was elected to serve a second term as European Athletics President last April at the continental governing body's Congress in Prague, where he stood unopposed.

In his absence, Dobromir Karamarinov is interim President.

Like Hansen, Karamarinov is also a member of the World Athletics Council and was first vice-president before Hansen became unwell.

European Athletics has not been short of issues to address without Hansen's leadership, with numerous events having to be cancelled or postponed in light of the coronavirus pandemic.

The European Athletics Championships are still scheduled to take place in Paris later this year, beginning on August 25, but this looks increasingly unlikely. 

The European Athletic Council is due to meet remotely on May 7 and 8, with the event in Paris set to be high on the agenda.

In addition to his work in athletics administration, Hansen is chairman of the multi-sport European Championships 2022 Board.

In his absence at present, Libor Varhaník - a European Athletics vice-president - is chairman of the European Championships 2022 Board.