Bitcoin XT, a new version, is currently being recommended by the currency’s chief scientist, Gavin Andresen.
And its developer, Mike Hearn, says its adoption is essential to ensure the currency can cope with growing demand.
But some, including a large number of bitcoin miners in China, are resisting XT because of how it might affect control over the currency.
Bitcoin’s blockchain – a digital ledger of all transactions made with the currency – is currently made up of 1MB blocks.
Bitcoin XT would enable these blocks to grow to 8MB.
But this would mean XT was no longer compatible with existing Bitcoin software, creating, its detractors say, two separate currencies and eroding trust in both.