Fankwe joined the Ammies last summer following a six-month stint at Championship side Watford as part of their academy setup.
The 21-year-old linked up with Salford's B team on a one-year deal and featured for the club in pre-season, but recently left the League Two strugglers to pursue other opportunities.
Earlier in his career, Fankwe spent five years at Nottingham Forest and established himself as a tough-tackling midfielder while coming through the ranks.
He joins a Basford side currently sat 18th in the Northern Premier League and outside of the relegation zone on goal difference alone.
Fankwe becomes the Lions' second arrival in a matter of days, with young Sheffield United defender Jack Waldron recently arriving on a work experience loan until the end of the season.
Photo credit: Salford City
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