(43)In order to avoid market fragmentation and ensure a level playing field for Union counterparties established in the Union on a global level, and acknowledging the fact that in some jurisdictions the exchange of variation and initial margin for single-stock options and equity index options is not subject to equivalent margin requirements, the treatment of those products should be phased-in. This phase-in period will provide time for monitoring regulatory developments in other jurisdictions and ensuring that appropriate requirements are in place in the Union to mitigate counterparty credit risk in respect of such contracts whilst avoiding scope for regulatory arbitrage.