The US president launched into lengthy attacks against the Democrats and the media at a rally for his supporters in Montana on Thursday evening.
Mr Trump used the occasion as an attempt to dispel unease surrounding Mr Putin’s intentions at the summit, which is due to take place in Finland later this month.
“I might even end up having a good relationship [with Mr Putin], but they’re going ‘well, president Trump, be prepared, president Putin is KGB’, this and that,” he told the rally.
“Do you know what? Putin’s fine, he’s fine, we’re all fine, we’re people. Will I be prepared? Totally prepared – I have been preparing for this stuff my whole life, they don’t say that.”
The pair are expected to meet one-on-one during the 16 July talks in a move that could ease strained US-Russian relations.
However, some international relations experts have warned Mr Putin may be able to “charm” his American counterpart into dropping long-standing positions held by his country.
Mr Trump also used the Montana rally to mock the Me Too movement against sexual harassment in the workplace and Democratic senator Elizabeth Warren.
The president referred to Ms Warren as “Pocahontas”, a swipe at her disputed Native American heritage, joking he would throw a DNA genealogy test at her during a debate.
“I will take one of those little kits they sell on television for two dollars – learn your heritage.” the president said.
“I am going to get one of those kits and in the middle of the debate, when she claims she is of Indian heritage because he mother said she has high cheekbones, that’s her only evidence.
“We will take that little kit, but, we will have to do it gently because we are in the Me Too generation, and we will slowly toss it, hoping it does hit her and injure her arm.”
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