British Prime Minister David Cameron and former London Mayor Boris Johnson have clashed on another day of intense day of campaigning for the EU referendum.
While the PM warned that Isis terrorists would be "happy" if Britain voted for Brexit, Johnson discredited Cameron's EU negotiations as "meaningless".
Cameron said: "Who would be happy if we left? Putin would be happy, I suspect Al Baghdadi would be happy."
The reference was to Abu Bakr al-Baghdadi, the leader of Isis (Islamic State).
Cameron gave a "myth-busting" speech on Brexit to members of the World Economic Forum.
The Prime Minister dismissed claims by the Leave camp that quitting would lead to a bonfire of regulations as "very, very weak" and insisted three million jobs were linked to membership.
Striking a deal on services from outside the EU would take longer than an agreement on goods because other countries, such as Italy, would want to gain advantage from Britain's exit, he warned.
"We may have a deficit in the sale of goods when it comes to the EU but we have a very large surplus when it comes to services and one of the things that I think we should fear is that, of course, if we left the EU they might offer us a deal on goods, but it might take a very long time before they offered a deal on services," he said.
"You can almost imagine the thrill and excitement of service businesses in Italy, France and Germany and elsewhere, saying okay, let's cut a deal with Britain on trade in goods but hold back the trade in services so we can fill all of those insurance and banking and other service industries at which Britain is so good."
Johnson criticised the PM's "meaningless" negotiations, insisting it was now beyond doubt the deal was a "fiction designed to bamboozle the public".
He said: "This is the biggest stitch-up since the Bayeux Tapestry. It stinks to high heaven.
"FTSE 100 chiefs are seeing their pay packets soar while uncontrolled immigration is forcing down wages for British workers.
"Now we learn that some fat cats have been secretly agreeing to campaign for Remain while angling for lavish Government contracts. It makes us look like a banana republic.
"And it is also now beyond doubt that the so-called renegotiation was a fiction designed to bamboozle the public.
"It was a meaningless mime, a ritual, a kabuki drama in which the outcome was utterly preordained. This is not the far-reaching and fundamental reform we were promised.
"The only safe way to take back control of our borders and our democracy is to Vote Leave on June 23."
Ukip leader Nigel Farage said of the PM: "I think increasingly in this referendum campaign he's looking like Dishonest Dave."