City Bridge Foundation, which is responsible for maintaining five bridges across the Thames, shared a photo of Robert from rope access contractor CAN Ltd deploying the straw.

Clause 36.2 of the Port of London Thames byelaws provides: “When the headroom of an arch or span of a bridge is reduced from its usual limits, but that arch or span is not closed to navigation, the person in control of the bridge must suspend from the centre of that arch or span by day a bundle of straw large enough to be conspicuous and by night a white light.”

Millennium Bridge will be closed for three weeks for cleaning and urgent repairs.