Glencore International Plc's debut today in Hong Kong has been graded the world's biggest initial public offering this year that could lure other investors from its competitors with its size and market value, analysts said.

In spite the downturn in the commodities market, Glencore is still optimistic that the demand for commodities will bounce back in the near term.

"All the markets are off around the world," Chief Executive Officer Ivan Glasenberg said in Hong Kong today. "We are still bullish on commodities. Of course, China may contract or slow down, but the demand for commodities still continues."

The Switzerland-based Glencore, began trading in London and with its market value of $58 billion has gained entry into the seven FTSE indices including the benchmark FTSE 100. The Hong Kong IPO is seen getting more attraction when it listed in the Hong Kong Stock Exchange on Wednesday.

Mr James Koh, an analyst with Kim Eng Holdings Ltd. in Singapore, who said some of his clients have asked about the possibility that some investors may make the switch from competitor Noble Group Ltd to Glencore because of its relative size now at $58 billion in capitalisation.

Mr Koh said and was quoted by Bloomberg: "People may want to switch as the latter is five times bigger" and has "improved financial muscle from the IPO. But it's not a mutually exclusive trade."

The Swiss trader, which deals in materials including coal, oil and grain, broke with more than three decades of operating as a closely held partnership in its IPO. Twelve cornerstone investors bought shares, including Abu Dhabi's Aabar Investments PJSC and BlackRock Inc.