The global economy could suffer losses of up to $50trn over five years if an extreme geopolitical conflict hits shipping lanes and snarls international trade, according to a modelling exercise for Lloyd’s of London.

A superpower invasion of a neighbouring country threatening to block key shipping routes would spark a broader global confrontation with cyber attacks, blockades and tit-for-tat sanctions, under the worst-case scenario drawn up by Lloyd’s and the Cambridge Centre for Risk Studies.