Ahmed Saadat (C), leader of the Popular Front for the Liberation of Palestine (PFLP), is escorted by Israeli police as he arrives to attend a hearing in his trial at the Magistrate's Court in Jerusalem on September 9, 2012. Israeli forces captured Saadat in March 2006 in a controversial raid on a Palestinian Authority prison in Jericho, accusing him of planning the 2001 murder of far-right Israeli tourism minister Rehavam Zeevi, which was carried out by four PFLP militants. AFP PHOTO/AHMAD GHARABLI

OTTAWA - The federal New Democrats refuse to criticize the Canadian Union of Postal Workers (CUPW) for sending a delegation to a controversial "Free Palestine" conference in Brazil last week.

Critics call the conference anti-Israel, but NDP leader Thomas Mulcair didn't take a position Monday on whether it was appropriate for CUPW to attend.

"You're going to have to ask the CUPW about that," said Mulcair.