Volkswagen made a long-awaited bid for MAN , valuing it at $20 billion and stepping up plans to merge the German truckmaker with Swedish rival Scania in which it also holds a stake.

Volkswagen, Europe's biggest carmaker, said on Monday it would offer MAN shareholders 95 euros per ordinary share and about 60 euros per preference share, in both cases less than the stock was trading at last week ahead of the bid.

This low-ball offer serves to start the takeover process but still have maximum flexibility, MM Warburg analyst Marc-Rene Tonn said.

The offer, which values the whole of MAN at 13.76 billion euros ($19.79 billion), was triggered when VW increased its stake above 30 percent, requiring a mandatory bid for the remaining shares under German rules.

The price represents a 1.6 pct discount to Friday's close of MAN common shares and 14.2 pct discount on Friday's close for the preference shares.

VW already owned 29.9 percent of MAN ordinary shares, which turned positive after the announcement, trading 2.1 percent higher at 98.52 euros at 1042 GMT. Volkswagen's blue-chip preference shares narrowed losses to trade 1.5 percent lower at 128.45 euros.

The timing of the offer is unexpected, but it was clear it would come eventually, MM Warburg's Tonn said.

Volkswagen has been toying with plans to create Europe's biggest truckmaker by merging MAN with Scania, in which it has a controlling stake.

(Additional reporting by Ludwig Burger and Arno Schuetze; Editing by Alexander Smith)

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