According to Annika Ström Melin, EU correspondent at Swedish newspaper Dagens Nyheter (DN), what already started with the refugee crisis, which has caused several European countries to reinstate temporary border controls, could also be aggravated by the terrorist threat.
"Due to the refugee crisis, different countries like Sweden, Germany or Austria have reinforced national border controls and it's obvious that what has happened in Paris will affect this, and different countries would like to know who is crossing their borders and why," Ström Melin told Radio Sweden.
She adds that this is connected with the fact the European Union's external borders have proven to be too permeable
According to Ström Melin, passport-free travel within the EU is currently one of the main discussion topics among EU politicians.
"I'd say it's one of the questions that is on the top of the agenda. Most countries would like in principle to defend the passport-free travel in the Schengen area because it's one of the big achievements and we doubt that the EU will go back 25 years," she says.
However, Ström Melin explains that the internal controls, which Sweden and other countries have already imposed, could be extended up to two years according to EU regulations.
"In theory, Schengen is still a working cooperation, but in practice, we already see there's really not so much left of that at the moment in Europe," she points out.
EU citizens wanting to move to other countries to look for a job or to study are not affected by these changes, but Ström Melin believes that even that freedom could be in jeopardy in the future.
"That is a right that is not affected by what is happening at the moment, it will just be more complicated. So in the short run there is no connection, but of course, in the long run, everything will be put on the table. As we know, this discussion has already started in the UK," she says.