Why is Trump welcoming the Saudi’s in from the cold?

As Donald Trump receives a royal welcome in Saudi Arabia, Sky's US correspondents Mark Stone and James Matthews discuss the $600bn (£451bn) deal signed between the two nations, and the love-in between the countries' leaders.  
  
Plus, Mark, who's in the Middle East with Trump, describes the reaction in the room when Trump announced he was lifting sanctions on Syria.   
 
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