The boy's father, whom she had divorced, had agreed to let her take their son to Turkey for a holiday, but the court found that she continued on to territory in Syria controlled by Islamic State.
The vaccination certificate would be signed by a Swedish authority with the help of a so-called encryption key so that its authenticity can be certified.
In December a majority of centre-right Swedish lawmakers said "Sweden should, like Finland , state that it is in favour of having a 'NATO option,'" referring to the defence alliance.