LONDON/FRANKFURT (Reuters) - Berlin has sounded out potential buyers for Uniper in a deal that could see the government selling its entire holding in the $18.8 billion energy utility, three people with knowledge of the matter said.

Germany's government, which owns 99.12% of the company after nationalising it in 2022 during Europe's energy crisis, is pursuing a partial stake sale, or re-IPO, of around 25% as a preferred option, but is also weighing exiting its holding in one go, the people said.

Parties that have been approached about a full sale include Canadian fund Brookfield, two of the sources said. A full sale to a private equity fund would be one of Europe's biggest in recent years.

Uniper nearly collapsed after its former main gas supplier, Russia's Gazprom, first curbed and later stopped deliveries after the outbreak of the Ukraine war, forcing the German government to step in to ensure energy security in Europe's biggest economy.

Germany's Finance Ministry, which oversees the government's Uniper stake, said on Monday the government was examining all scenarios to cut its stake, with no firm decision regarding timing and structure. It reiterated that the leading option for the re-privatisation was selling shares via the equity market.

Uniper and Brookfield both declined to comment.

The sale talks come as Germany prepares for a snap election next month. While a new government's plans for the holding are as yet unclear, it will still be held to EU regulations obliging it to cut its Uniper stake to a maximum 25% plus one share by 2028.

Uniper is currently valued at 18.4 billion euros ($18.8 billion), but any stake sale could come at a discount because the group's small free float may not properly reflect its actual value, Reuters reported previously.

One of the three people, and a fourth source, said a deal would require parliament to first pass a law that allows Uniper to restart paying dividends, a right it was stripped of as part of Berlin's 13.5 billion euro bail-out.

Berlin had initially targeted a deal in the spring but that timeline was drawn up before the current government collapsed, making it more likely that such a change will be done by the next administration, one of the people said.

The current government is expected to at least make an attempt to lift the ban on dividends before the election, a timeline that is considered ambitious, a government source said. However, any deal is now more likely to happen after the European summer, the sources said.

The new targeted timing also takes into account the formation of the new government and potential changes around the sales process.

Deliberations are at an early stage and there is no certainty around how a deal will look and when it will take place, the people said. All four were speaking on condition of anonymity because the process is private.

While a full sale would generate higher proceeds right away, it would remove the possibility of Berlin benefiting from any future gains in the Uniper share price, the people said.

($1 = 0.9790 euros)