Ukraine, currently engaged in the historically inconvenient business of repelling a full-scale Russian invasion, has found time to generate a corruption scandal involving Andriy Yermak, President Volodymyr Zelenskyy's powerful chief of staff. Pressure is mounting on Zelenskyy to address the scandal at a moment when Western allies are already scrutinising whether their weapons funding is being administered with appropriate seriousness of purpose.

The timing is, charitably speaking, suboptimal. European leaders have just gathered at 10 Downing Street to discuss bolstering Ukraine's missile defenses, while simultaneously having to field uncomfortable questions about whether the government they are arming has its own house in order. Zelenskyy, who built his political brand on an anti-corruption platform, now faces the particular humiliation of having that brand interrogated while Russian artillery provides an unsympathetic backdrop.

Ukraine has historically ranked among Europe's most corrupt nations, a distinction that predates the current war by several decades. Western patience, already strained by the financial enormity of the support package, is not a renewable resource. Whether Zelenskyy moves decisively against his own inner circle or opts for the time-honoured tradition of vigorous-sounding investigations that conclude quietly remains the defining question.