US e-commerce giant Amazon has been criticised for selling Christmas ornaments with images of the Nazi concentration camp Auschwitz-Birkenau, calling them inappropriate.

The museum at the site of the former camp in southern Poland tweeted screenshots of the items showing train tracks and barracks and requested that Amazon remove them from their site.

"Selling 'Christmas ornaments' with images of Auschwitz does not seem appropriate. Auschwitz on a bottle opener is rather disturbing and disrespectful," the museum tweeted.

The museum added later that Amazon appeared to have removed the items - but then posted a follow-up saying it had discovered others.

Those include a "disturbing" mousepad and a ceramic Christmas ornament with a freight car used for deporting Jews for extermination.

Nazi Germany set up the death camp after occupying Poland during World War II.

The Holocaust site has become a symbol of Nazi Germany's genocide of six million European Jews, with one million killed at the camp between 1940 to 1945.

More than 100,000 non-Jews also died there, according to the museum. An estimated 232,000 of the victims were children.