Just before Donald Trump takes the presidential oath of office next month, the Obama administration plans to release a full report on Russian connections to cyber attacks during the election, officials said Friday .

Trump has cast doubt on the Kremlin’s involvement in politically charged hacking and fake news efforts prior to this year’s election while leading members of Congress have called on the administration to share what it knows about the Russian connection and pushed for a wider investigation, leading to a potentially fiery showdown over the issue. And such a public divide between the president-elect and intelligence agencies is unusual and dangerous, say experts.

“To evaluate Congress’s response appropriately, we would like all Members to have a comprehensive understanding of what the U.S. Intelligence Community knows regarding Russia’s involvement in these actions and attempts to interfere in our election,” the lawmakers wrote this week in an open letter to President Barack Obama.

Officials sometimes purposely share with Congress “only what is necessary for them to perform proper oversight,” partially as a safeguard against unintentional leaks, says Chris Finan, a former White House cybersecurity advisor and CEO of Bay Area security startup Manifold Technology. But in this case, Finan says it was more likely that intelligence agencies are still working to establish precisely how various efforts to influence the election link back to the top levels of the Russian government.

“They’d want to try to find deliberate command and control links—instances where people were directed by a Russian official,” he says. “I think that there’s probably a lot of interest and focus in, are these proxy groups operating on their own based on what they thought Moscow would want them to do or were they acting on a directive from somebody in the Russian government.”

Prominent Democrats in the House of Representatives introduced a bill on Wednesday calling for a bipartisan commission to investigate Russian attempts to influence the election. Maryland Rep. Elijah Cummings cited October statements from intelligence officials blaming Russia for hacks targeting Democratic Party servers and subsequent leaks of embarrassing emails.

“The head of the National Security Agency said there is no doubt that this was a targeted and conscious effort to achieve a specific result,” Cummings said in a statement. “And the Intelligence Community also said that they believe that only Russia’s senior-most officials could have authorized these activities.”