Frontline Plc, the shipping giant controlled by billionaire John Fredriksen, gave up plans to buy Euronav NV and create the world’s largest publicly listed oil-tanker company after opposition from one of Belgium’s oldest shipping families.

Frontline — listed in both Norway and the US — won’t make an offer for all outstanding shares of Euronav and is formally withdrawing its earlier intention, the company said late Monday. Frontline shares surged as much as 22% in Oslo on Tuesday, while Euronav dropped 21% in Brussels.

The termination brings to an end, at least for now, a battle between two shipping magnates for control of Antwerp-based Euronav. Fredriksen last year bought a stake in Euronav, before proposing to combine it with Frontline. But Compagnie Maritime Belge, which steadily increased its holdings in Euronav in the last few months, has been opposed to the plan from the outset, arguing that it doesn’t create shareholder value.

Euronav will examine Frontline’s letter and reserves all rights and actions after the termination, it said in a statement on Tuesday. Regardless, the “supportive and sustainable fundamental factors of the tanker markets have started to deliver what Euronav and most sector commentators believe will be a prolonged upcycle,” the company said.

The announcement “is a clear negative for Euronav as the combination would have created significant opportunities for both companies,” Degroof Petercam analyst Luuk van Beek said. The company’s shares have a 13% downside, while Frontline has a 35% upside, Fearnley Securities’ Oystein Vaagen wrote in a note.

Both companies have large fleets exposed to a tanker market that is likely to remain robust for the foreseeable future, Evercore ISI analysts Jonathan Chappell and Sean Morgan said in a note. The companies are set to generate strong cash flow and provide generous returns for shareholders, they added.