The failure of FFA and PFA to agree a new CBA has resulted in the Matildas cancelling their U.S. tour. no_source

SYDNEY -- Australia's two-match series in the United States to face the Women's World Cup champions has been called off as negotiations continue over a new collective bargaining agreement.

Professional Footballers Australia (PFA), a union representing male and female players, said the tour was called off late Wednesday, a day after players refused to show up for practice in Sydney.

PFA chief executive Adam Vivian informed Football Federation Australia (FFA) of the players' decision immediately after a meeting of the Matildas early on Wednesday.

"The players are currently uncontracted, and are under no obligation to participate in any Matildas-related activities," Vivian said in a statement.

"The players feel they have been left with no option other than to take this course of action. They were hopeful that FFA's position would alter following yesterday's breakdown in negotiations. However, the interim letter agreement offered to the players this afternoon, with a 6 p.m. deadline, proved this had not been the case."

FFA has today withdrawn the Westfield Matildas from two matches against @FIFAWWC winners USA http://t.co/VFQMdp57Dh pic.twitter.com/j0yWxlRO22 - Football Australia (@FFA) September 10, 2015

FFA chief executive David Gallop confirmed that the tour would not go ahead late on Thursday.

"Sadly, the Matildas will not be playing the USA because FFA and the A-League clubs can't meet the PFA's unaffordable demands in relation to the level of the salary cap for A-League players," Gallop said at the FFA's press conference.

"This is a competition in which the clubs lost a collective $17 million last season.

"What we have today is an extraordinary situation in which the two male playing groups in the Socceroos and A-League continue to be paid by FFA and A-League clubs, but the female players aren't being paid. This could have been fixed today if the PFA had accepted the interim deal.

"The Matildas alone are the ones being directly affected as a result of the whole of game CBA talks not being resolved."