Suppose the British pound (GBP) is pegged to the euro (EUR). You think there is a 5% probability that the GBP will be devalued by 10% over the course of the next month. What interest differential...

Suppose the British pound (GBP) is pegged to the euro (EUR). You think there is a 5% probability that the GBP will be devalued by 10% over the course of the next month. What interest differential would prevent you from speculating by borrowing GBP and lending EUR?