Clifford Chance (CC) and Simpson Thacher & Bartlett have acted on a $21bn (£14bn) Chinese financing.

The money was raised by the Aluminium Corporation of China (Chinalco) ahead of its expected $19.5bn (£13.1bn) investment in mining giant Rio Tinto.

Simpson Thacher advised Chinalco, fielding a multi-office team led by Beijing-based corporate partner Douglas Markel, alongside UK finance partner Euan Gorrie in London, New York-based corporate partner Alan Klein and the firm's Washington DC managing partner Peter Thomas, who advised on regulatory aspects. Chinese firm Commerce & Finance also took a role for Chinalco.

Chinalco secured the loan from a syndicate of banks led by China Development Bank, advised by CC and King & Wood. Beijing-based project finance partner Bruce Schulberg and Beijing and Hong Kong managing partner Stephen Harder led the CC team.

The financing, finalised by the end of last month, includes $19.5bn that will be used for the investment, while $1.5bn (£1bn) has been set up as a standby facility for related expenses.

CC and Linklaters advised Chinalco and Rio Tinto respectively on the investment, which is awaiting shareholder approval. London corporate partners Kathy Honeywood and Nigel Wellings and Beijing-based Rupert Li led for CC, while London corporate partner James Inglis led for Linklaters.

The move represents the largest outbound investment ever put forward by a Chinese company and would see Chinalco increase its stake in Rio Tinto from 9% up to 18%.