Hold fire on this - it's just a bold statement so far from our mate George - sounds like he's still on the banker-bashing adgenda for the benefit of joe public. Nobody knows what will be introduced, how, when, what weight or size of aircraft, whether public transport, private or both, inbound, outbound, domestic, international, EU/UK or any other weired and dodgy registers (less than half UK-based private 'executive' aircraft are on EU27 registers), all turbine, piston and turbine, jet only, tax on pax (APD), new or increased fuel duty - Avgas and/or Jet, VAT say on charters with more than 'X' passenger seats or over a certain weight etc. etc.
As those US Senators say, there's one hell of a lot of known unknowns.
They'll come up with a number of options, go out to consultation, realise it's impossible to administer, monitor or control, find that there are a multitude of loop-holes and international laws that render any proposal unenforcable and shelve the whole idea. It is more than likely to cost more in administration, monitoring and implimentation than they will make - and you can bet your bottom dollar that not a penny will go to any environmental pot anyway.
Ask for transparency and they'll all get awkward and give up.