Pass distorted or undistorted points to (E)PnP?

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I have one RGB-D camera and one RGB and I want to estimate the camera pose.

Working on the two RGB images, I'm using ORB for feature detection and descriptors extraction and Flann for feature matching. Then, having the 3D-2D correspondences, I use EPnP for camera pose estimation.

My question regards the undistortion of the images. Considering that the EPnP implementation in OpenCV undistorts the 2D points, should I pass zero distortion coefficients to EPnP and undistort both images before detecting and matching the features (so I use the undistorted points as inputs for the EPnP)? If passing the distortion coefficients to the EPnP, should the input points of 2D or 3D image be distorted or undistorted?