A towering runaway cruise ship rammed into a sightseeing boat on Italy’s Venice canal Sunday morning — just days after a similar crash left 28 feared dead in Hungary.

Video shows the luxury MSC Opera unable to stop and repeatedly blaring its horn as it hits the much-smaller River Countess, eventually pushing it into the dock despite the efforts of towboats to stop it.

Four female tourists were injured on the sightseeing boat that had 110 passengers, officials said.

MSC Cruises blamed a mechanical problem on its ship, which can carry over 2,675 passengers in 1,071 cabins, as it tried to dock in the Giudecca Canal.

Italian officials immediately called for all such cruise ships to be banned from using the major thoroughfare that leads to Saint Mark’s Square

“Today’s accident in the port of Venice proves that cruise ships shouldn’t be allowed to pass down the Giudecca anymore,” insisted Italy’s transport minister, Danilo Toninelli.

“After many years of inertia, we are finally close to a solution to protect both the lagoon and tourism.”

The accident came just three days after a tour boat carrying 33 South Korean tourists sunk in Hungary after getting hit by a ship on the Danube River.

Seven were pronounced dead and 21 are still missing, although authorities have admitted it seems unlikely more survivors will be found, with high water levels stumping rescue operations.

Hungarian police launched a criminal investigation and confirmed that the captain of the cruise ship, a 64-year-old named Yuriy C., had been detained and questioned.

With Post wires