Updated

Survivors and families of those killed in last year's Christmas market truck rampage in Berlin will meet with Chancellor Angela Merkel for the first time amid continued anger at German authorities' failure to stop the attack and handling of the aftermath.

Monday's meeting was announced shortly after the injured and bereaved sent Merkel a blistering open letter, telling the long-time German leader it would have shown "respect" if she had reached out to them sooner.

The group also cited numerous official inquiries and media reports revealing how dozens of government agencies bungled the surveillance of perpetrator Anis Amri, a Tunisian asylum-seeker and petty criminal German police suspected had ties to Islamic extremists.

Families will unveil a memorial Tuesday, the anniversary of the attack, for the 12 people killed.