Two British Airways jets have been grounded, as the investigation into Alexander Litvinenko’s death spreads yet further. 33,000 passengers over 221 flights are being contacted ‘as a precaution’.

But pilots and cabin crew wear badges that measure their dose of radiation, since they are naturally exposed to more due to being high up in the atmosphere for long periods of time. Why didn’t their badges show a greater than usual exposure, and hence detect this problem before now?

The only explanation I can think of is that the radiation is very short-range, and the cabin crew were never close enough to be affected. The radiation on Polonium-210 is very short range. Have we discovered how the murder weapon entered the country?

And guess the top destination where those planes have been been flying? Yep, Moscow. It’s looking like Mr Putin can’t ignore this investigation any longer – if the Polonium is shown to have likely come from Moscow, he’s going to have to co-operate, rather than just issue denials. But hours before this story hit the media, Mr Putin announced he’s now decided to cancel his meeting with Mr Blair.

Co-incidence?