Swiss multinational Glencore on Tuesday announced a modification of its proposed transaction with Canadian miner Teck Resources, introducing a cash element for those investors that may prefer a full coal exit.

In a letter addressed to Teck chairperson Sheila Murray and CEO Jonathan Price, Glencore CEO Gary Nagle said the commodities giant would offer investors in the Canadian company 24% of MetalsCo and $8.2-billion in cash.

"Glencore continues to believe that CoalCo's combined thermal and coking coal assets would position it as a leading, highly cash-generative bulk commodity company which would attract strong investor demand given its yield potential. However, we acknowledge that certain of your investors may prefer a full coal exit and others may not desire thermal coal exposure," he said.

Glencore's initial all-share offer offer, valued at about $22.50-billion, includes a plan to create two standalone companies – MetalsCo and CoalCo.

Teck, for its part, is planning a restructuring in which it would spin off its steelmaking coal unit to focus on copper and other industrial metals. In an investor call on Monday, Price reinforced Teck's rejection of the unsolicited offer, telling shareholders its restructuring plan was the only viable option.