UPDATE 1-China's CEFC investigation hits $9 billion Russian oil deal

* First payment tranche made before deal stalled -sources

* Acquisition seen as sign of growing Russia-China ties

* Deal stalled due to investigation into CEFC boss -sources

By Dmitry Zhdannikov

LONDON, March 22 (Reuters) - Chinese conglomerate CEFC hadalready started paying for a stake in Russian oil giant Rosneftwhen authorities took its chairman Ye Jianming away, halting the$9.1 billion deal in its tracks, according to three sourcesclose to the matter.

The fate of the deal, one of the largest Chinese investmentsin Russia, has become a litmus test of how far President XiJinping's government is prepared to go with a crackdown onfinancially risky activities among big-spending conglomerates.

The acquisition of the stake in Russian state oil firm isseen as strengthening relations between Russia and China, theworld's top energy exporter and top energy consumer.

CEFC China Energy was buying the 14.16 stake from aconsortium including Swiss trader Glencore. It hadtransferred the first tranche of payment before it ceased allcommunications, the sources told Reuters.

The sources declined to say how much had been paid. One saidthe fact some money has changed hands would make it moredifficult for any party to back out of the deal.

CEFC founder and chairman Ye was put under investigation byChinese authorities over suspected economic crimes, Reutersreported at the beginning of March, and he will step down fromhis position at the firm.

Rosneft representatives have since travelled to China butfailed to get any update from CEFC on the stake acquisitiondeal, according to the sources.

"The other party (CEFC) has just vanished," one source said.

Rosneft and Glencore declined to comment, while CEFC did notrespond to a Reuters request for comment.

Another of the sources said it was difficult to predict howthe deal would unfold. "One thing is clear though. The Kremlinwants China to own a stake in Rosneft. And China has long saidit wants to boost Russian energy ties," he added.

The Chinese foreign ministry and the Chinese nationaldevelopment and reform commission, a state economic managementagency, did not immediately respond to requests for comment. TheKremlin declined to comment.

RAPID GROWTH

The investigation into Ye, who founded CEFC in 2002,followed mounting concerns among Chinese authorities about thefinances and opaque ownership of the Shanghai-based private firmwhich has grown from a niche fuel trader into an oil and financeconglomerate with assets across the world.

An investment firm owned by the Shanghai government has beentasked with evaluating CEFC's financial position as part of arestructuring and takeover process.

State-controlled China Huarong Asset Management Co has takena 36.2-percent stake in CEFC Hainan International, the unit thatis acquiring the Rosneft stake.

Complications to the deal could prove a blow for Rosneftboss Igor Sechin, a close ally of Russian President VladimirPutin. Sechin is keen to attract new foreign investment as a wayof showing the Kremlin oil producer is not crumbling under thepressure of Western sanctions but is growing.

In 2016, Sechin clinched a deal with Glencore and Qatar'sstate fund QIA to sell 19.5 percent in Rosneft for 10.2 billioneuros. Qatar contributed 2.5 billion euros with the rest mainlycoming from Russian banks.

Less than nine months later, CEFC agreed to buy out themajority of the stake with QIA keeping its stake intact ataround 5 percent, equal to its initial contribution.

(Additional reporting by Vladimir Soldatkin and Aizhu Chen;Writing by Dmitry Zhdannikov; Editing by Pravin Char)