The Arabic television station Al Jazeera has denied a Japanese news agency report which quoted it as saying that three Japanese hostages held in Iraq had been released.
"We did not issue such a report," an Al Jazeera official told Reuters, referring to a report by Jiji news agency.
Japanese TV earlier said the three Japanese civilians kidnapped in Iraq were safe near the Iraqi town of Falluja, but government officials could not confirm the report and it was unclear when they would be released.
Al Jazeera said on Saturday that Iraqi militants holding the hostages would free them in response to a call from the Muslim Clerics Association in Iraq.
The Iraqi group had originally threatened to "burn them alive" unless Tokyo pulled out its troops from Iraq within three days.
Japanese Prime Minister Junichiro Koizumi, facing the toughest test of his political career, vowed not to give in to their demands.
Japan has about 550 troops in the southern Iraq city of Samawa, where they are involved in reconstruction and humanitarian work, the Japanese army's riskiest and most controversial overseas deployment since World War Two.