Jeremy Corbyn’s Labour Party suffered a major setback in Thursday’s local elections in Britain as it lost to the Scottish National Party (SNP) in Scotland and Plaid Cymru in Wales and lost control of councils across England. The gloomy results were expected, so Corbyn’s allies in the bitterly-divided Labour Party were keen to make the point that Labour had not lost control of as many councils in England as might have been expected. Corbyn’s problem is that Labour’s one bright spot with Sadiq Khan’s expected success in the election as London mayor is that any success was less about the party and more about a personal vote for Khan in what became a bizarrely personal feud between him and the Conservative candidate Zac Goldsmith.

British opposition parties historically pick up seats in mid-term local elections, and Labour’s failure has to be disturbing to its supporters. Rather than gaining several hundred local council seats, as would be normally be expected, Labour has lost council seats in a way that no opposition has lost in 30 years. In Scotland, Labour was pushed into third place after the Conservatives and dominated all the voting in Glasgow, which was once a Labour stronghold.

The SNP was delighted with the result in the Scottish parliament as they become the first party to win a majority for three times running. In the English council elections, the Conservatives were delighted with their modest success as they prepare for a much more high-profile judgement in the European Union (EU) referendum on June 23. They will be analysing the local results to try to see how the voters have judged Prime Minister David Cameron’s enthusiastic endorsement of staying in the EU, in the referendum that is due in just a few weeks, and they will extrapolate that into their hopes for the next general election.

Corbyn now faces a challenge as the massive vote for his leadership from party members has not translated into electoral success. Ever since he was voted in against all expectations, a large number of senior Labour figures have been waiting for him to stumble and this vote may be their moment. There is very little chance of a coup against Corbyn until after the EU referendum, but a variety of Labour would-be contenders have been preparing to challenge their leader after the referendum, with an eye to being in place before the party conference after the summer break.