A condolence register with the signatures of Dutch King Willem-Alexander and Queen Maxima (right page) lies in front of a hedge of compassion prior to a commemoration ceremony for the people who died in the crash of Malaysian Airlines flight MH17, in Nieuwegein, near the central city of Utrecht, the Netherlands, on Friday. Photo: AFP

Relatives of the victims of flight MH17 that was shot down over Ukraine a year ago joined emotional memorials on Friday as calls mounted for a UN-backed tribunal to prosecute those responsible for the tragedy.

All 298 passengers and crew, the majority Dutch, died on July 17 last year when the Malaysia Airlines Boeing 777, on a flight from Amsterdam to Kuala Lumpur, was downed over rebel-held in eastern Ukraine.

Kiev and the West have accumulated evidence pointing at the rebels, saying they may have used a BUK surface-to-air missile supplied by Russia to down the plane. But Moscow denies involvement and instead blames Ukraine's military.

Flags flew at half-mast in the Netherlands as about 1,600 relatives and friends gathered at a closed ceremony in Nieuwegein to mourn the victims of the disaster, while a national memorial ceremony was held in Canberra.

Dutch Prime Minister Mark Rutte told the NOS public broadcaster ahead of the ­service, "I still think about it every day."

In Canberra, Australian Prime Minister Tony Abbott unveiled a plaque in memory of those killed, including 38 Australian citizens and residents. "Today we remember our dead, we thank those who brought them home. But most of all, we acknowledge the suffering of the bereaved," he told the crowd, which included 120 relatives of those who perished.

During the emotional ceremony, tears flowed as photographs of the smiling faces of victims were flashed up on to big screens followed by the word "remember."

Australian Paul Guard, who lost his parents Roger and Jill, made the journey to the Australian capital with nine other family members.

"It will be a difficult day but hopefully a useful part of the healing process," he told reporters ahead of the service.

Malaysian relatives also took part in an emotional memorial service in Kuala Lumpur last week, demanding justice and answers about who is responsible for the disaster.