TEL AVIV (REUTERS) - United States President Joe Biden will seek to reduce direct contact, such as shaking hands, during his visits to Israel and Saudi Arabia this week as part of enhanced Covid-19 precautions, White House officials said on Wednesday (July 13).

The apparent shift in policy could enable Mr Biden to avoid being photographed shaking hands later this week with Saudi Crown Prince Mohammed bin Salman, known as MBS.

"We're in a phase of the pandemic now where we are seeking to reduce contact and to increase masking... to minimise spread," US national security adviser Jake Sullivan told reporters on Air Force One on a flight to Israel when asked about reports that Mr Biden would not be shaking hands on the trip.

"I can't speak to... every moment and every interaction and every movement. That's just kind of the general principle we're applying," he added.

Mr Biden, who called the Saudi government a "pariah" for its role in the 2018 murder of Washington Post journalist and political opponent Jamal Khashoggi, is reluctantly meeting the Crown Prince, who US intelligence believe was behind the killing, during his stop this week in Saudi Arabia.

"The White House is desperately trying to avoid the picture of Biden shaking hands with the Crown Prince, especially after the Washington Post editorial condemning meeting with MBS. Covid is a simple excuse but it won't change the fact of the meeting," said Mr Bruce Riedel, a foreign policy fellow at the Brookings Institution.

Mr Biden departed for Israel late on Tuesday after spending part of the late afternoon and early evening shaking multiple hands on the White House South Lawn during a congressional picnic.

Mr Biden fist-bumped the Israeli delegation on arrival, but later talked closely with Israeli Prime Minister Yair Lapid as the two leaders stood shoulder to shoulder, with arms behind each other's back.

The US President shook hands with former prime minister Benjamin Netanyahu, now the opposition leader, and Defence Minister Benny Gantz.

The White House on Tuesday urged Americans over age 50 to get vaccination boosters against Covid-19 as the fast-spreading Omicron BA.5 subvariant takes hold across the US.

Mr Biden will participate in a bilateral meeting with the Saudi king and Crown Prince on Friday, but in recent weeks has sought to emphasise the meeting with a broader set of Gulf leaders.

White House spokesman Karine Jean-Pierre said no news conference was scheduled during Mr Biden's Saudi Arabia trip.