Swimming New Zealand's chief executive Mike Byrne says SPARC's decision to withold funding follows news media speculation and questions about the sport's high performance programme.
Swimming's budgeted to receive $1.65 million a year in 2011 and 2012, but the government sport's funding body has guaranteed only $825,000 for the next six months.
It also wants the programme reviewed independently by April 30.
When he retired recently the former Commonwealth Games champion Moss Burmester criticised the coaching structure and said Swimming New Zealand no longer had swimmers' best interests at heart.
But Byrne says he doesn't know how much influence that had.