British and American regulators are at odds over the approach to testing blockchain-based financial securities, according to sources. The UK supports using a 'sandbox' environment for testing tokenized securities, while the US Securities and Exchange Commission (SEC) favors an 'exemption' approach, aligning with the US crypto industry's preferences. This disagreement emerged during a January meeting of a working group formed last September to enhance digital asset cooperation. Despite consensus on harmonizing stablecoin regulations, the two sides have yet to agree on specific testing methods. A recommendation report is anticipated before summer.