“I don’t think it’s a crazy idea,” Gen Sir Chris Deverell, former commander of the UK’s Joint Forces Command, said on the BBC Today programme.

Under a Ministry of Defence Life Extension Project, the fleet will reduce from 227 to 148 vehicles, releasing 79 Challengers for possible export to Poland. The remaining 59 are used for training and as a reserve. According to Janes, the UK has 227 Challenger 2s, operated by three tank regiments, with 56 vehicles each. The Challenger 2 MBT is currently in service with the British Army. “What the Ukrainians want - and I think are now going to get - is a collection of guarantees from like-minded countries about what we can do to back them up with weaponry, with training, and with intelligence-sharing,” Johnson said. Johnson said it is essential to step up immediate military support to Kyiv. British Prime Minister Boris Johnson has been careful to provide only defensive weapons to avoid provoking Moscow. Sending tanks to “backfill” for T-72s supplied to the Ukrainian Army will come close to crossing a red line.

Russian invasion: Situation report day 411

British new main battle tank