Combination photo shows the logos of Glencore and Xstrata
Glencore-Xstrata merger delayed .

Glencore has postponed the date to complete its takeover of Xstrata for the third time in the absence of approval for the deal from Chinese authorities.

Following the news, the company's stock declined on the London Stock Exchange, falling 3.81 percent to 372.75 pence as at 9:47 am.

The company informed its shareholders that the deal cannot be completed by the "long stop date" of 15 March, announced in January. Also, the company has not set a new deadline for completing the deal.

The £50bn ($75bn, €58bn) merger, creating a natural resources mammoth with 130,000 employees in more than 40 countries, was earlier approved by the European and South African authorities. The mega merger would bring together Xstrata's coal, copper, nickel and zinc mines with Glencore's expertise and market position in trading hundreds of commodities.

Glencore already had a 34 percent stake in Xstrata before the merger deal was announced. The deal faced several hurdles, including opposition from Qatar Holdings that had a 12 percent stake in Xstrata. Glencore had to raise the share exchange ratio to 3.05 new shares for every Xstrata share from an earlier ratio of 2.8 in order to get Qatar's nod.

Further, Xstrata shareholders were not happy with a pay plan to retain key executives in connection with the merger. About 80 percent of the shareholders were not in favour of the pay scheme.

The merger does not significantly impact competition but China can consider domestic industrial policy while considering approval, The Wall Street Journal had earlier reported, citing Berwin Leighton Paisner LLP lawyer Dave Anderson.

Both Glencore and Xstrata are already selling minerals in China and the merged company expects to raise its market share in the country. Nevertheless, they do not have operating assets like mines and smelters in the region.