BEIJING (Reuters) - China called on other countries to treat its companies "objectively and fairly" in overseas acquisitions bids on Tuesday as Chinese home appliances maker Midea <000333.SZ> looked set to secure a controlling stake in German robotics giant Kuka <KU2G.DE>.

Midea looked set to secure a 52.8 percent stake in Kuka on Monday after shareholders Voith and Friedhelm Loh sold their stakes to the Chinese bidder. Midea launched a 4.5 billion-euro ($5 billion) offer for Kuka in May.

The bid is the largest yet by a Chinese buyer for a German industrial technology company, and it has sparked protests by some Berlin politicians concerned about key know-how falling into foreign hands.

"We hope that all countries can treat overseas mergers and acquisitions by Chinese enterprises objectively and fairly, and give fair treatment to these kinds of normal business activities, and also create a transparent and reasonable business environment," said Chinese Foreign Ministry spokesman Hong Lei in a regular briefing in response to a question about the deal.

He said Chinese companies acted independently in terms of their business decisions, including overseas acquisitions.

Kuka already sells 25 to 30 percent of its robots in China, the firm's chief has said.

China, which has made increased automation in manufacturing a top priority, is the world's biggest industrial robot market, although growth in demand slowed to 17 percent last year from 56 percent a year earlier.

The government has also worked to encourage companies to buy up strategic assets in a number of sectors including food and technology, though regulators in the west have sometimes baulked at Chinese bids to acquire closely guarded or unique technologies.

(Reporting By Megha Rajagopalan; Editing by Greg Mahlich)