European countries need to cooperate more in testing preparedness for cyber attacks against critical infrastructure, according to an EU advisory body.

Governments should work more with the private sector to run cyber exercises, the European Network and Information Security Agency (ENISA) said in a statement on Thursday.

"There is an essential need to intensify public–private cooperation on cyber exercises, as the ownership of most of the critical information infrastructures lies in private hands," ENISA said.

Over the last decade, 41 per cent of cyber exercises have only involved the public sector, said ENISA.

Cyber exercises have increased in number over the past two years, with 71 per cent taking place between 2010 and 2012. Member states are running more exercises due to an increasing threat of cross-border attack coupled with a greater emphasis on strengthening information security, ENISA said.