Speaking to reporters aboard Air Force One on his way to New Jersey, Trump also said he would discuss the conflicts in Syria and Ukraine and other international issues with Putin during the July 16 summit.
"I’ll talk to him about everything," Trump said.
"We’re going to talk about Ukraine, we’re going to be talking about Syria. We’ll be talking about elections ... we don't want anybody tampering with elections."
Russia has denied US intelligence agencies’ assessment that Moscow sought to interfere with the 2016 US election to boost Trump’s prospects of becoming president.
After Trump and Putin met briefly in Vietnam in November 2017, Trump was criticized in the United States for saying he believed Putin when he denied Russian meddling.
Trump denies wrongdoing and calls an investigation into possible collusion between his presidential campaign and Russia a “witch hunt.”
Crimea separated from Ukraine and rejoined Russia in March 2014 following a local referendum, with almost 97 percent of the residents voting for the reunification.
The US have imposed several rounds of economic sanctions against Russia, insisting the peninsula was illegally annexed.
Meanwhile, Russia's military intervention in Syria to support President Bashar al-Assad is another major issue facing the two countries’ relations.
Asked if the United States would recognize Crimea as part of Russia, Trump said: "We’re going to have to see."
He gave a similar answer when he was asked if he would lift the sanctions on Russia. “We’ll see what Russia does,” Trump said.