White House chief of staff John Kelly on Wednesday plans to address the swift leak of guidance issued to President Trump not to congratulate Russian President Vladimir Putin on his election “win” earlier in the week when they spoke on the phone, according to a report.

Kelly is furious, the official said, and will address the matter as aides look into who could have leaked the national security advisers’ Tuesday warning to Trump: “DO NOT CONGRATULATE,” CNN reported . Trump disregarded the guidance and congratulated Putin, and also ignored a request that he condemn the poisoning of a former spy and his daughter in England, which several countries say is the work of Russia.

“This is unacceptable,” the official told CNN, adding that some believe the leak was made as an attempt to embarrass the president.

The White House declined to comment, saying officials "cannot comment on alleged classified deliberative documents allegedly provided to the President."

However, a White House official did not dispute the leak or the alleged language used in the warning to Trump.