Russian energy company Gazprom sent Kiev a $7 billion bill for unused gas from 2012 that was mandated under a take-or-pay contract with the Ukrainian government.
Kiev has moved for relief from its energy ties with Russia. It says a 2009 natural gas deal is too expensive when compared with other European contracts.
Stavitsky was quoted by the BBC as saying there were "no grounds" for the bill. The $7 billion fee accounts for about 4 percent of Ukraine's gross domestic product.
"We have replied that we do not deem it expedient to honor the $7 billion bill, that is, to pay it because we have no reason to do so," he said.
Ukrainian President Viktor Yanukovych this week said his government has had "no support (or) even sympathy" from his European counterparts regarding the gas row.
Former Ukrainian Prime Minister Yulia Tymoshenko is serving a seven-year prison sentence after being convicted on charges she abused her authority when she helped broker the 2009 agreement. European leaders say the charges are politically motivated.
Tymoshenko lost a bruising election battle to Yanukovych in 2010.