Chinese home appliance maker Midea formally launched a €4.5 billion ($5.1 billion) offer for German industrial robot maker Kuka on Thursday, reiterating its aim to acquire more than 30 per cent of the company.

Midea, which already owns 13.5 per cent of Kuka, said it was offering €115.00 ($129.5) per share in an offer running from June 16 to July 15 and welcomed a diversified shareholder base with a high free float. Kuka shares closed at €106.05 ($120.01) on Wednesday.

The Chinese firm also confirmed it planned no control agreement or other agreement with Kuka. The latter's chief executive, Till Reuter, told shareholders at their annual meeting last month that Midea's offer supported Kuka's strategy.

Midea had announced its planned bid a month ago, causing a furor among German politicians who fear the loss of a key industrial technology company but are reluctant to intervene in commercial deals. The offer represents a premium of 36 per cent to Kuka's share price before Midea declared its intentions.

Sources in the ruling German coalition told Reuters this week that Midea wanted a stake of no more than 49 per cent and would resell any shares it acquired beyond that threshold.

The Midea offer to shareholders made no mention of any such upper threshold. Acquiring 30 per cent would oblige Midea to bid for the rest of the company, under German takeover law.

Kuka is the biggest German industrial technology company to be targeted by a Chinese buyer in a rising wave of deals over recent months.

Major shareholders Voith and Friedhelm Loh have not said whether they plan to sell their respective stakes of 25 and 10 per cent, and Kuka's management has yet to make a recommendation. - Reuters