FILE PHOTO: Director General of MI5 Andrew Parker delivers a speech in central London, on the security threat facing Britain October 17, 2017. REUTERS/Stefan Rousseau/Pool/File Photo

BERLIN (Reuters) - The head of Britain’s MI5 spy agency said on Monday Britain’s case that Russia was responsible for the poisoning of a former spy, Sergei Skripal, and his daughter had strengthened in recent weeks.

Andrew Parker told reporters in Berlin that the investigation was continuing, but he did not want to signal to Russia “what we know and what we don’t know.”

He noted the British government provided sufficient information to convince all 28 European Union members about its position several weeks ago. “The case has if anything got stronger since then, but I can’t explain why it is I say that today,” he said.