BERLIN/FRANKFURT/LONDON (Reuters) - Shell's planned sale of a stake in the Schwedt refinery in Germany is being delayed by pending lawsuits by third parties, two people familiar with the matter said, stalling a divestment the company has waited years for.

The deal has been complicated by Berlin's stripping Schwedt's majority owner Rosneft of its control, but not its shares, following the severing of energy ties between Germany and Moscow in 2022.

Shell's planned sale of its 37.5% stake to Britain's Prax Group, was expected to close in the first half of 2024 "subject to partner rights and regulatory approvals", but completion is still pending.

The sources said the agreement has a clause stating that if the deal isn't closed by mid-September the parties need to agree an extension or renegotiate.

The delay stems in part from pending lawsuits, including an attempt by Rosneft to prevent the sale to Prax, one of the sources said, efforts that a German court this week said had little chance of success.

While the stake's value was put at around 155 million to 190 million euros ($173-212 million) it was attributed a negative equity value of around 14 million euros, according to sources and deal documents reviewed by Reuters.

Shell said it is continuing to work with Prax on finalising the sale. Prax Group said it would not make any further comment until the transaction was completed.

Rosneft did not reply to a request for comment.

Concerned about potential political repercussions, Berlin has so far shied away from expropriating Rosneft in Germany, something it can theoretically do under tightened energy security regulation.

Shell has been wanting to get rid of its stake in the refinery, which supplies around 90% of Berlin's fuel, for years and initially hoped to sell it to Vienna-based group Alcmene in 2021, a deal that was preempted by Rosneft.

A November ruling by the Berlin administration court that has given Alcmene, in theory, the green light to acquire Shell's stake in Schwedt has further complicated the process, the source said.

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