I'm really talking about retail savings accounts: most banks in the UK pay give 2%-3% on deposits up to a cap, with no interest paid on funds deposited above th

I'm really talking about retail savings accounts: most banks in the UK pay give 2%-3% on deposits up to a cap, with no interest paid on funds deposited above the cap. However, it's often possible to get around the cap by opening multiple accounts. You can stash amounts into the mid tens of thousands like this, but for higher values it gets a bit trickier. These are retail products. It's true that an increase in the yield on government bonds would move the exchange rate, but the kind of institutional investors that move money in enough bulk to affect an exchange rate have little interest in retail deposit accounts.