ICAO Annex 1
1.2.2.2 Recommendation.— A pilot licence issued by a
Contracting State should be rendered valid by other
Contracting States for use in private flights.
The UK complies with this recomendation in respect of Non Part 21 aircraft and validaes ICAO licences in accordance with the ANO Article 150.
What safety reason is there for complying with a recomendation in respect of one group of aircraft whilst ignoring it for Part 21 aircraft?