* Not yet clear when Rachel Empey to join Fresenius-report
* Fresenius CEO said CFO position had been filled
* Fresenius CEO: not yet clear when unnamed CFO would start
* Telefonica D. says Empey's contract runs until end-2018 (Adds comment from Telefonica Deutschland, details on Empey's career)
FRANKFURT, April 27 (Reuters) - Fresenius has tapped Telefonica Deutschland finance chief Rachel Empey to fill the same position at the diversified German healthcare group, German business monthly Manager Magazin cited sources as saying on Thursday.
Fresenius Chief Executive Stephan Sturm, who was promoted from chief financial officer last June, said earlier this week the company had found someone for the CFO position but that it was unclear when the current employer would let the executive go.
The magazine said that Telefonica Deutschland - having just lost its chief executive officer Thorsten Dirks to airline Lufthansa where he will run the Eurowings division - was unwilling to immediately release Empey from her contract.
Negotiations were at a final stage, it added.
Telefonica Deutschland said in a written statement in response to the report that Empey's contract runs until the end of 2018, adding that there had been no talks between the two companies. It declined to comment further.
A spokesman for Fresenius would not comment on the Manager Magazin report.
Fresenius this week stepped up its dealmaking, agreeing to buy U.S. generic drugmaker Akorn for $4.75 billion (4.37 billion euros) and the biosimilars arm of Germany's Merck KGaA.
Takeovers have been part of Fresenius's growth strategy under previous boss Ulf Mark Schneider, now leading Nestle , but Sturm is lifting the pace, having bought a Spanish hospital chain for 5.8 billion euros since taking over in June.
Empey, who holds an Oxford degree in mathematics, has been in various finance and controlling positions at Telefonica Deutschland and parent Telefonica, having worked previously as an auditor at Ernst & Young and as business analyst at Lucent Technologies.
Reporting by Ludwig Burger and Peter Maushagen; Editing by Maria Sheahan and Jane Merriman