WASHINGTON — White House officials on Monday defended President Donald Trump’s explosive claim that Barack Obama tapped Trump’s telephones during last year’s election, although they won’t say where that information came from and left open the possibility that it isn’t true.

In televised interviews, Kellyanne Conway and Sarah Huckabee Sanders said Trump firmly believes the allegations he made on Twitter over the weekend. The aides said any ambiguity surrounding the issue is all the more reason for Congress to investigate the matter.

“We’d like to know for sure,” Sanders, deputy White House press secretary, told NBC’s “Today” show.

The House and Senate intelligence committees, and the FBI, are investigating contacts between Trump’s campaign and Russian officials, as well as whether Moscow tried to influence the 2016 election. On Sunday, Trump demanded that they broaden the scope of their inquiries to include Obama’s potential abuse of his executive powers.

When asked where Trump was getting his information from, Sanders said the president “may have access to documents that I don’t know about.”

Likewise, Conway said that “credible news sources” suggested there was politically motivated activity during the campaign. But Conway also said Trump might have access to other information she and others don’t.

“He is the president of the United States,” Conway told Fox News’ “Fox & Friends. “He has information and intelligence that the rest of us do not.”