UPDATE - UK: Allegations on Kashoggi's disappearance 'serious'

UPDATES WITH COMMENTS BY GERMAN FOREIGN MINISTRY; EDITS THROUGHOUT

By Ahmet Gurhan Kartal

LONDON (AA) - London said Monday it is working “urgently” to help find answers to last week’s “serious” case of a journalist who went missing after entering the Saudi Consulate in Istanbul.

"These are extremely serious allegations," said a British Foreign Office representative in a statement.

"We are aware of the latest reports and are working urgently to establish the facts, including with the government of Saudi Arabia," said the statement.

Berlin also expressed grave concern about the disappearance of Saudi-born Jamal Khashoggi, a columnist for The Washington Post.

Christopher Burger, a Foreign Ministry spokesman, told reporters that Germany expects all relevant parties to help clarify the incident.

He warned against speculation, as the investigation is ongoing.

Khashoggi has been missing since he entered the Saudi Consulate in Istanbul on Oct. 2.

Turkish police investigating the case said in a statement Saturday that 15 Saudis, including several officials, arrived in Istanbul on two planes and entered the consulate while Khashoggi was inside.

Istanbul prosecutors are investigating the incident, while the consulate said on Twitter that it was working in coordination with Turkish authorities.

Turkey on Monday said it expects "full cooperation" from Saudi authorities in finding the missing journalist.

*Ayhan Simsek contributed to this story from Berlin.