The winger has been frozen out of the Spurs first-team in recent months following a fall-out with coach Nathan Gardiner.
During that time he has been working with the club's development squad and on Monday he posted what appeared to be a goodbye message to the Under-21 team on the social networking site.
He wrote: "Been an absolute pleasure playing with the u21 boys the last 3 or 4 months!"
Newcastle are understood to be the only interested party and a deal had looked close last week, with Townsend set to join the north east side on loan for the remainder of the campaign before a permanent summer switch.
The deal was plunged into doubt amid reports the clubs were unable to reach an agreement on the final fee but it is now claimed a compromise has been reached and the 24-year-old is expected to secure a move to St James' Park in the coming days.
Townsend again featured for Spurs' Under-21s when they lost 2-0 against Liverpool on Monday evening.