The European Union's lower court has annulled the bloc's decision to keep Hamas on a list of terrorist organisations, but maintained the measures against the group for a period of three months or until appeals against the decision were closed.

It stressed that Wednesday's decision to remove Hamas from the list was based on technical grounds and does "not imply any substantive assessment of the question of the classification of Hamas as a terrorist group".

Hamas's military wing, the al-Qassam brigades, was added to the European Union's first-ever terrorism blacklist drawn up in December 2001 in the wake of the September 11 attacks on the United States.

The EU then blacklisted the political wing of Hamas in 2003.

"The General Court finds that the contested measures are based not on acts examined and confirmed in decisions of competent authorities but on factual imputations derived from the press and the Internet," the court said.

Instead, such an action had to be based on facts previously established by competent authorities. it said.

The court said it was nevertheless maintaining the effects of the measures in order to ensure that any possible future freezing of funds would be effective.

Israeli Prime Minister Benjamin Netanyahu called on the European Union on Wednesday to keep Hamas on the list.

"We expect them to immediately put Hamas back on the list," Netanyahu said in a statement. "Hamas is a murderous terrorist organisation which in its charter states its goal is to destroy Israel."