President Donald Trump allegedly sought to convince the Justice Department to drop charges against Turkey’s Halkbank at the request of President Recep Tayyip Erdogan, The Wall Street Journal reported in an overview of former national security adviser John Bolton’s tell-all book.

The Justice Department has levied a series of charges against Turkey’s state-owned Halkbank for its role in a 2012 Iran sanctions evasion scheme. Bolton claimed that Erdogan, who allegedly used the bank for improper personal dealings, had frequently asked Trump to drop the case against Halkbank official Mehmet Atilla. The former national security adviser said Trump had asked him to call former Acting Attorney General Matthew Whitaker to get him to drop the case. Bolton says he never followed up on the request.

Why it matters: Ankara’s frequent attempts to get the Trump administration to drop the Halkbank charges had caught the attention of some US lawmakers even before the explosive allegations in Bolton’s book.

“Reporting on John Bolton’s book confirms that Donald Trump attempted to interfere in a criminal investigation into the largest sanctions violations scheme in US history as a favor to Turkish President Erdogan,” said Ron Wyden of Oregon, the top Democrat on the Senate Finance Committee. “I have been investigating potential political interference by Donald Trump as it relates to Turkey and sanctions enforcement, and this damning evidence corroborates what my investigation has uncovered to date.”