The legal requirement to have two signatories on a payment has recently been repealed (2013?) as the introduction of payment by eBanking has become more common.
However, some Hall Constitutions, Charities and Funders (such as the National Lottery) still require 2 signatures, so you should check your own particular situation and act accordingly.
Some Banks are able to offer Accounts where an electronic countersign authorisation can be added to an electronic payment before the payment will be made. At this point in time (mid 2014), our understanding is as follows: