LONDON (Reuters) - U.S. buyout fund KKR and China’s Tencent Music Entertainment Group are exploring rival bids for up to half of Vivendi’s iconic Universal Music division, a deal potentially worth up to 20 billion euros ($23 billion), sources told Reuters.

French tycoon Vincent Bollore, who controls Vivendi with a 25 percent stake, is in the process of selecting banks to oversee a partial sale of Universal Music Group (UMG), two sources familiar with matter said.

Sell-side banks are expected to be appointed in March, with a process likely to kick off in the second quarter, they said.

But informal discussions with potential bidders are underway as banks are trying to gauge appetite for the unit.

UMG is the world’s biggest music label ahead of Sony Music Entertainment and Warner Music, and is home to artists like Lady Gaga, Taylor Swift, Drake and Kendrick Lamar.

Vivendi, KKR and Tencent declined to comment.

Vivendi shares were the top gainers on France’s benchmark CAC index on Thursday, up 3.4 percent at 1019 GMT, after Reuters first reported KKR and Tencent’s interest.

Analysts have expressed different views on UMG’s valuation.

JPMorgan’s media analyst Daniel Kerven recently described the business as “a unique asset – under-monetized, must-have global content that is strategic to the tech giants and can’t be replicated”. He pegged UMG’s fair value at 44 billion euros.

FILE PHOTO: The logo of Universal Music Group (UMG) is seen at a building in Zurich, Switzerland July 25, 2016. REUTERS/Arnd Wiegmann/File Photo

That is higher than rival estimates. Deutsche Bank put it at 29 billion euros, Goldman Sachs at 35 billion euros and Exane BNP Paribas at 25 billion euros.

Vivendi’s boss Arnaud de Puyfontaine said in 2017 that the unit could be worth more than $40 billion.

At the time, Vivendi was exploring a possible stock market listing, a plan later shelved amid challenges in eking out big profits in the sector, with many customers still unwilling to pay much for songs they can hear free on the radio, in music blogs or on free apps.

Universal will generate roughly 1.5 billion euros of free cash flow excluding interest payments in 2023, Deutsche Bank forecast.

Tencent Music Entertainment Group, a subsidiary of China’s biggest gaming and social media firm Tencent Holdings Ltd, has an existing licensing agreement with Universal and wants to strengthen its collaboration with a partial acquisition, the sources said, cautioning that no deal was certain.

But industry bidders may find it hard to negotiate a joint venture deal with Bollore as they would not be able to secure a majority stake and have a meaningful say on UMG’s strategy going forward, the sources said.

Bollore wants to stay in the driving seat, they added.

Some private equity funds including U.S.-based KKR are willing to enter an equity partnership with Bollore and help fund UMG’s international expansion, even if they won’t be able to take full control, the sources said.

KKR previously entered a joint venture deal with Bertelsmann, Europe’s largest media company, to back music rights management company BMG. It proved to be a lucrative investment for KKR, which doubled its money when it sold its stake back to Bertelsmann in 2013.

One of the sources said other big buyout funds who are technology-savvy and have conducted similar investments in the TMT sector have shown interest in making a bid for UMG.

For private equity investors the deal offers a high-profile platform to tap into the music industry, which is recovering from a 15-year long downturn and has grown for the past three years.

Global recorded music revenues rose 8.1 percent in 2017 to $17.3 billion, according to record industry trade group IFPI.

Streaming revenues represented the bulk of the growth, with sales up more than 41 percent, driven by 176 million paid subscribers.

UMG owns 4 percent of Spotify, the world’s most popular paid music streaming service, a stake that Vivendi executives have always described as a core investment, ruling out any plans to cash out.