WATCH: Sessions told Trump's fired Attorney General to stand up to President in 2015

Trump's unconfirmed pick for Attorney General encouraged recently-fired Sally Yates to say "no" during her Senate hearing two years ago

WATCH: Sessions told Trump's fired Attorney General to stand up to President in 2015

Senator Jeff Sessions speaks during Sally Yates’s Senate confirmation hearing in 2015

President Donald Trump's as-of-yet unconfirmed pick for Attorney General Jeff Sessions told former Acting Attorney General Sally Yates to "watch out" for the president - in 2015.

During Yates’s Senate confirmation hearing in 2015, Mr Sessions told the recently-unemployed Yates "to watch out" as she would be put in a position where she would have to stand up to then-President Barack Obama on orders he made.

"You have to watch out, because people will be asking you to do things that you just need to say no about. Do you think the attorney general has a responsibility to say no to the president if he asks for something that’s improper?

"But if the views that the president wants to execute are unlawful, should the attorney general or the deputy attorney general say no?"

In response, Ms Yates said: "I believe that the attorney general or the deputy attorney general has an obligation to follow the law and the Constitution, and to give their independent legal advice to the president."

Earlier today, the President fired Ms Yates after she refused to defend his new immigration policy.

In a letter to lawyers quoted by the New York Times, Ms Yates argued: "At present, I am not convinced that the defense of the executive order is consistent with these responsibilities, nor am I convinced that the executive order is lawful."