Head of UK Air Traffic Control confirms regular UFO activity

This was on the Today Programme, BBC Radio 4 in the UK, on August 17th 2012.
Richard Deakin is Head of National Air Traffic Services (NATS), the British agency responsible for national Air Traffic Control and national air safety.
He was being interviewed about general air safety practices – and then, before he goes, the interviewer Simon Jack asks a tangential question (apparently prompted by his children as a favour) about UFOs. Deakin confirms on air that Air Traffic Control routinely tracks objects that do not “conform to normal traffic patterns”, with a frequency of roughly “one a month”.
(Note: He was not talking about balloons, birds, insects or chinese lanterns: unsurprisingly, Air Traffic Control radar systems do not track these)

Hear the relevant segment of the interview here:

http://news.bbc.co.uk/today/hi/today/newsid_9745000/9745210.stm

Complete interview taken from the Today audio page at:

http://news.bbc.co.uk/today/hi/today/newsid_9744000/9744906.stm