Notorious Coolock hood Aymen Shebani (30) had been charged with the attempted murder of his former associate Simon O'Connor in Newry on St Patrick's Day last year.
Both men were key members of the criminal enterprise led by Mr Big, the north Dublin gangster who is the number one target for gardai.
Shebani was also charged with two counts of threatening to kill O'Connor (32) in relation to the alleged street attack that left O'Connor with life-threatening injuries.
The 30-year-old Irish criminal of Libyan descent spent weeks on remand in the North's highest security Maghaberry Prison before being bailed.
He was due to go on trial in the New Year. but the Northern Ireland Courts Service has confirmed that the charges have been withdrawn.
No reason has been given as to why the charges have been dropped.
Sources say that, before the stabbing incident, O'Connor and Shebani were close associates, members of the crew led by Mr Big, who is suspected of ordering the murder of Real IRA terror chief Alan Ryan.
Gardai want to question Shebani about a string of serious crimes and it is understood that he is still living in the Newry area.
His former pal O'Connor is the chief suspect for stealing a garda patrol car and racing it across the border while being pursued by 20 garda cars and the garda helicopter in December of last year.
O'Connor allegedly managed to get behind the wheel of the patrol car at the Round Towers filling station in north Co Dublin just moments after being arrested.
It is understood that gardai were examining his Lexus car at the scene and left him unattended in the patrol car.
After he stole the garda car, a massive pursuit operation was put into place involving 20 marked and unmarked cars as well as the garda air support helicopter.
The suspect drove at "huge speed" northbound up the M1 motorway, crashing through barriers on the toll booths at Drogheda, Co Louth.
The barrier and garda car were damaged in the incident, but the driver kept speeding up the motorway.
O'Connor, who is originally from Donnycarney, managed to avoid being arrested by gardai and made his way across the border. The car was recovered near Newry.
Like Shebani, O'Connor has a string of previous convictions.
He was ordered was ordered to pay a total of €50,000 to two sisters whom he terrorised during a burglary at their north Dublin family home in March, 2004.
O' Connor -- who had heroin addiction issues -- pleaded guilty to false imprisonment and aggravated burglary at Blackheath Road, Clontarf, on January 30, 2004.
He also admitted the burglary of publican Mark Grainger's family home in Portmarnock and the theft of his car on March 7, for which he received a five-year sentence.
Aymen Shebani has been a priority target for gardai and the Police Service of Northern Ireland for years.
It is understood that he has spent most of the past five years based between Co Donegal, and Co Down, while making regular trips to his criminal associates in Dublin.
In September 2011, he was jailed in Derry for six months for failing to declare a stash of almost €70,000 in euro and dollar notes found in a case and wardrobe.
As part of the same operation, PSNI officers recovered a garda uniform that had been stolen in a burglary in Letterkenny, Co Donegal in November 2009.