* China's HNA now Deutsche Bank's largest shareholder
* HNA investment at an uncertain time for Deutsche Bank
* Regulator says positive that capital invested in banks (Updates with full quote, background)
FRANKFURT, May 9 (Reuters) - China is welcome to invest in German financial firms, Germany's top market watchdog said after Chinese conglomerate HNA Group raised its stake in Deutsche Bank.
An acquisition spree by HNA reflects a broader Chinese push into financial services as Beijing encourages its corporate sector to expand overseas, although such moves have faced increased regulatory scrutiny in the United States and Europe.
"We believe it is fundamentally positive that capital is being invested in German banks. This of course includes foreign capital and of course Chinese capital," BaFin President Felix Hufeld said on Tuesday.
"There is no black list of countries that are not allowed to invest with us. In this regard, this is a welcome development," he said at the regulator's annual press conference.
Last year, BaFin gave a green light to China's Fosun to take over the small private bank Hauck & Aufhäuser.
HNA's investment in Deutsche Bank, which it revealed last week had risen to just below 10 percent, comes at a time of heightened uncertainty for the bank.
Germany's largest lender is grappling with a strategic turnaround, an uncertain global economy and the impact of Britain's departure from the European Union. The disclosure in a U.S. regulatory filing showed that HNA had become Deutsche Bank's biggest direct shareholder, slightly ahead of funds controlled by Qatar's former Prime Minister Sheikh Hamad bin Jassim al-Thani who last year increased their stake, including options, to just under 10 percent.
Deutsche Bank sees the HNA and Qatari stakes as a vote of confidence that should encourage other investors, big and small.
Chinese investors are also said to have shown some interest in buying a stake in the troubled HSH Nordbank. HNA and Chinese insurer Anbang have both made inquiries about Nordbank, two financial sources have told Reuters. (Reporting by Tom Sims, Andreas Kroener and John O'Donnell; Editing by Maria Sheahan and Alexander Smith)