July 17 (Reuters) - U.S. President Joe Biden on Saturday differed with Saudi Arabia on discussions at a bilateral summit about the 2018 murder of journalist Jamal Khashoggi, a key controversy between the two nations.

Answering reporters as he arrived at the White House from his first Middle East trip as president, Biden disputed the Saudi foreign minister's account that he did not hear Biden blame Saudi Crown Prince Mohammed bin Salman for the killing of the Washington Post columnist, a harsh critic of his native Saudi Arabia.

Asked whether the minister of state for foreign affairs, Adel al-Jubeir, was telling the truth in recounting the exchange between Biden and the crown prince, the president said "No".

U.S. intelligence agencies believe the crown prince ordered the killing of Khashoggi, a U.S. citizen, which the de facto Saudi ruler denies.

Jubeir said the crown prince, known as MbS, had told Biden the kingdom had acted to prevent a repeat of mistakes like Khashoggi's killing and that the United States had also made mistakes.

The minister told Fox News on Saturday that he "didn't hear that particular phrase" from Biden blaming the crown prince.

Biden, asked whether he regretted exchanging a first bump with MbS on Friday, replied: "Why don't you guys talk about something that matters? I'm happy to answer a question that matters."

(Reporting by Shivam Patel in Bengaluru; Editing by William Mallard)