Ukraine's Defence Force has just tweeted again, calling for all civilians to join regardless of their age - even if they're minors, presumably.
The statement, attributed to the Commander of Troops, Yuri Galushkin, reads:
"Today, Ukraine needs everything. All procedures for joining are simplified.
"Bring only your passport and identification number.
"There are no age restrictions."It tells people if they face problems signing up, they just need to refer to this official tweet.
https://www.bbc.com/news/live/world-europe-60517447 10:21