Shares in commodity trader Glencore opened at 548 pence, more than three percent above their offer price in grey market trading on Thursday.

The Swiss-based firm, which is set to propel straight into London's FTSE-100 index of bluechip shares when it begins unconditional trading on May 24, raised $10 billion in its London and Hong Listing.

If it exercises a 10 percent overallotment option that total will rise to $11 billion, making it London's largest ever initial public offering.

(Reporting by Kylie MacLellan, Editing by Clara Ferreira-Marques)