"I strongly condemn any form of terrorism and extremism. Our hearts are with the victims' families and France," Cerar said on his Twitter profile.

Pahor sent a letter of condolences to French President Francois Hollande describing the attack as "an act of terrorism that deserves the strongest condemnation."

"I have been deeply shaken by news about last night's tragedy in Nice, France, the heart of Europe. Innocent victims have been killed: children, families, people who celebrated and lived the values of the free world," he said according to the president's office.

To honour the victims, the National Assembly observed a minute's silence at the outset of the final day of the regular sitting before summer recess.

"We are condemning in the strongest terms this mean, abject and unpardonable act," Speaker Milan Brglez said, expressing the assembly's sincerest sympathies with the French nation and everyone affected by the tragedy.

On the occasion, he also expressed commiseration with everyone who "lost their loved ones in the recent acts of terror and cowardice in Istanbul, Dhaka and Baghdad".

"Our thoughts stand in defence of human dignity, freedom and humanness," Brglez said before inviting the house to observe a minute's silence in commemoration of the victims of the Nice attack.

Shock at the tragedy was also expressed by MPs at the joint session of the committees of foreign policy and EU affairs with Democrat (SDS) MP Branko Grims commenting that Europe should not be a battlefield and Jožef Horvat of the fellow opposition New Slovenia (NSi) urging greater investment in security in Europe.

According to the Foreign Ministry, no Slovenian nationals were hurt or reported missing in the latest terrorist attack.

At least 84 people are dead, including many children, and dozens injured, including 18 in a critical condition, after a 19-tonne truck plunged through a crowd during Bastille Day celebrations.