Donald Trump has blamed Joe Biden and Kamala Harris for last month’s failed assassination attempt against him by accusing them of making it difficult for the Secret Service to protect him.

The Republican presidential nominee’s claim – for which he offered no evidence – was made on the television talkshow Dr Phil, hosted by Phil McGraw, on Tuesday. The remarks follow disclosures that several Secret Service agents from the Pittsburgh field office had been placed on administrative leave after the 13 July shooting.

At a campaign rally in Butler, Pennsylvania, last month, Trump was grazed on the ear by a bullet after a 20-year-old gunman opened fire from the roof of a nearby building. One rallygoer, Corey Comperatore, was killed and two others were seriously wounded. The gunman was shot dead by a Secret Service officer at the scene.

“When this happened, people would ask, whose fault is it?” Trump told McGraw. “I think to a certain extent it’s Biden’s fault and Harris’s fault. And I’m the opponent. They were weaponising government against me, they brought in the whole DoJ to try and get me, they weren’t too interested in my health and safety.