Republican U.S. presidential nominee Donald Trump speaks at Youngstown State University in Youngstown, Ohio August 15, 2016. REUTERS/Eric Thayer

WASHINGTON (Reuters) - Republican presidential nominee Donald Trump is expected to receive his first national security briefing this week from intelligence officials, sources said on Tuesday.

Representatives from the Office of the Director of National Intelligence will give the New York businessman a wide-ranging briefing on foreign policy and national security issues and current threats, but not ultra-sensitive information about ongoing U.S. undercover spy operations or the identities of intelligence sources and methods, according to a source familiar with the matter.

The Director of National Intelligence serves as the head of the U.S. intelligence community, advising the president, the National Security Council and the Homeland Security Council on matters related to national security.

“I know that there will be a briefing, and it will be this week,” Trump foreign policy adviser Walid Phares confirmed in an email to Reuters.

ABC News reported that Trump will be accompanied to the briefing by two top advisers, General Michael Flynn, a former Defense Intelligence Agency chief, and New Jersey Governor Chris Christie, who heads Trump’s White House transition team.

A source familiar with briefing procedures said that it was unclear whether Flynn and Christie currently have the type of active security clearances that would allow them to participate in such a briefing but that they likely held them in the past.

Neither Flynn nor a campaign spokeswoman immediately responded to requests for comment on the briefing.

Officials have expressed some concern about whether Trump, who has never held public office, will be able to keep sensitive secrets he might hear to himself. Republicans have pointed out Democratic nominee Hillary Clinton, when secretary of state, used a personal email system to transmit allegedly sensitive government messages, some of which were classified “Top Secret” after the fact.

There was no indication on Tuesday that Clinton has thus far requested such a briefing for herself, sources familiar with the briefing process told Reuters.