Iran has condemned the jihadist attacks in Tunisia, Kuwait and France, saying they were "contrary to the teachings of Islam," in statements released Saturday by the foreign ministry.

The killings were not apparently coordinated, but the Islamic State group claimed the atrocities in Tunisia and Kuwait, just days before the first anniversary of it declaring a "caliphate" in Iraq and Syria.

Kuwait is to hold a mass funeral on Saturday for 26 people killed in a suicide bombing at a Shiite mosque claimed by the Islamic State jihadist group.

The interior ministry said in a statement early Saturday that 26 people and the bomber were killed and 227 others wounded in one of the country's worst bombings and its first ever on a mosque.

Kuwait said Saturday that it had raised security at oil facilities in the emirate to maximum level after a deadly mosque bombing claimed by the Islamic State group.

Friday's suicide attack on a mosque in the capital used by members of Kuwait's Shiite minority killed 26 people and wounded 227, and was one of the deadliest in the emirate's history.

Security agencies have intensified their measures throughout Lebanon in light of Friday's terror attacks in Kuwait and Tunisia, reported As Safir newspaper on Saturday.

A security source told the daily that the agencies went on alert in anticipation of the occurrence of new terrorist attacks.

Italy raised its terror alert level on Friday after deadly attacks in France, Tunisia and Kuwait.

"No country is without risk, we have raised the level of alert to re-sensitize those units charged with protecting sensitive places," Interior Minister Angelino Alfano said.

Spain raised its terror alert level from medium to high on Friday after deadly attacks in France, Tunisia and Kuwait, its Interior Minister Jorge Fernandez Diaz said.

"Considering the proximity of our country to the places where some of these attacks took place, it has been proposed to raise the anti-terrorist alert" from three out of five, or 'medium', to four or 'high', he told a news conference. 

Muslim clerics condemned three militant attacks in Tunisia, Kuwait and France on Friday that killed dozens of people including holidaymakers.

Al-Azhar, a leading Sunni Muslim institution based in Egypt, said the "heinous" shooting at a Tunisian coastal resort which killed 28 people, mostly Europeans, was a "violation of all religious and humanitarian norms."

The United States condemned "heinous attacks" in France, Kuwait and Tunisia on Friday but said it had seen no evidence that they were directly coordinated.

"Our thoughts and prayers are with the victims of these heinous attacks, their loved ones, and the people of all three countries," the White House said.

U.N. Secretary-General Ban Ki-moon and the Security Council on Friday strongly condemned the attacks in France, Kuwait and Tunisia and said those responsible must face justice.

One person was decapitated in southeastern France, while in Tunisia gunmen killed at least 37 people at a beach resort, and 27 people died in a suicide bombing claimed by Islamic State jihadists in Kuwait.

European leaders condemned Friday's "heinous" suspected Islamist attack on a gas factory in France and massacres in Tunisia and Kuwait, vowing to maintain a united front against "barbarism".

One person was decapitated near Lyon in southeastern France while in Tunisia gunmen killed at least 27 people at a beach resort and in Kuwait a suicide bombing at a mosque claimed by Islamic State jihadists killed 13.