Ukip MEP Patrick O'Flynn today said he had stepped down as the party's economics spokesman and apologised to leader Nigel Farage for calling him "snarling, thin-skinned and aggressive".
Nigel Farage said he had accepted the resignation with "sadness", adding that O'Flynn will remain a member and MEP.
Raheem Kassam, a senior adviser to Nigel Farage, is no longer working for Ukip, the party's leadership has confirmed.
A Ukip spokesperson said: "Raheem Kassam no longer works for UKIP. End of."
The move comes amid a row over the party's direction, with the election campaign chief Patrick O'Flynn criticising key figures around the Ukip leader - believed to include Kassam and party secretary Matthew Richardson.
Speaking about his departure, Mr Kassam said his contract with Ukip was always due to end at the end of May.
The Democratic presidential candidate may also have shown his cards on his choice of running mate.
The US president also shared a post on Twitter accusing Dr Anthony Fauci of misleading the public over hydroxychloroquine.
Fears over an impending second wave of coronavirus dominates Wednesday’s front pages.