A judge on Wednesday blocked the auction of a Jewish World War II artifact estimated to be worth millions that a Holocaust-survivor’s son says was improperly put on the block.

Rabbi Hyman Rubin — the son of late Rabbi Menacham Mendal Rubin who survived Auschwitz — filed suit Monday to block a Sept. 19 auction at Guersney’s from selling a relic his father was gifted after the war.

The piece is an 8-foot-tall Krumbach Torah Ark — an ornamental housing for religious scrolls — that Menacham brought with him when he moved from Germany to Brooklyn in the 1940s.

The artifact is estimated to sell for between $1 and $2 million.

The dad later entrusted it to Rabbi Shaul Shimon Deutsch for display at the Living Torah Museum in Brooklyn with the condition he wouldn’t sell it without permission, the suit claimed.

The father has since passed and Hyman claims he was not consulted before the museum gave the Ark to the auction house — and he and his congregation want to the relic back.

Hyman’s lawyer, Baruch Gottesman, said Hyman doesn’t want the piece to be sold to just anyone.

“For the plaintiffs, this is not a financial injury … if it’s lost, it’s lost forever,” Gottesman said.

Deutsch’s lawyer, Geoffrey Bowser, claimed that the contractual condition that the Ark not be sold was added after Deutsch signed the deal with Menacham in 2006.

“We dispute the authenticity of the document,” Bowser said.

An expert is testing the age of the inks of the signature and the agreement to determine if Bowser is correct.

Deutsch’s side claims the museum needs the proceeds of the sale to function, but Manhattan Supreme Court Justice Andrew Borrok said he didn’t see any harm in delaying the sale until the dispute was resolved.

“It’s in everybody’s interest that the title gets cleared up. Respectfully, I am granting the TRO,” Borrok said.