NEW YORK, United States (AFP) — Donald Trump on Thursday sought douse the outcry provoked by his challenge to Russia to hack into Hillary Clinton’s emails, by saying he was being sarcastic.

“Of course I’m being sarcastic,” the Republican presidential nominee told Fox News one day after making the sensational suggestion at a news conference.

“Russia, if you’re listening, I hope you’re able to find the 30,000 emails that are missing. I think you will probably be rewarded mightily by our press,” the New York billionaire had said Wednesday.

The Clinton campaign slammed his remarks as a “national security issue.”

“This has to be the first time that a major presidential candidate has actively encouraged a foreign power to conduct espionage against his political opponent,” Clinton’s senior policy advisor Jake Sullivan said.

Trump accused the Democrats of trying to deflect from the contents of leaked Democratic Party emails, which have deeply embarrassed the Clinton campaign and which her team said were hacked by Russia.

The emails, leaked by WikiLeaks, showed the extent to which party leaders sought to undermine Clinton’s rival Bernie Sanders, even questioning his religious faith, and forced the Democratic National Committee chairwoman to resign.

“They don’t even know frankly if it’s Russia, they have no idea if it’s Russia, if it’s China, if it’s someone else. Who knows who it is,” Trump told Fox.

“The real problem is what was said on those emails from the Democratic National Committee,” he added. “What they said on those emails is a disgrace and they’re just trying to deflect from that.”

Trump supporter and former New York mayor Rudy Giuliani, himself a controversial figure on the national stage, leapt to the Republican nominee’s defense.

“He was joking around,” Giuliani told CNN. “If he tells you I’m joking, you take him at his word.”