BRUSSELS (AFP) - French Prime Minister Manuel Valls said on Wednesday that hostages had been taken in a "terrorist" attack on a museum in the Tunisian capital in which at least seven foreigners were killed.

"I condemn this terrorist attack in the strongest terms. There has been a hostage-taking, without doubt tourists have been affected, killed," Valls said in Brussels after talks with European Commission President Jean-Claude Juncker.

"This attack cruelly illustrates the threat that we are all confronted with in Europe, in the Mediterranean, around the world. France, Tunisia and Europe will act together to fight terrorism," Valls added.

Juncker said he was also following events in Tunis, adding that he did not want to say much "because there is a hostage situation".

Tunisian officials said at least seven foreigners and a Tunisian were killed in the brazen daytime attack on the Bardo Museum, adding that the "majority" of tourists were evacuated but refusing to confirm reports that hostages were taken.

France has taken a strong stance on terror-related issues since January's deadly Paris attacks on the Charlie Hebdo satirical magazine, a Jewish supermarket and a policewoman.