The divisive political climate in America hung over the Oscar nominees luncheon on Tuesday as Academy Awards president Cheryl Boone Isaacs opened the gathering with a call for tolerance and freedom of expression. "Today we celebrate you, your work and your achievement, but each and every one of us knows that there are some empty chairs in this room, which has made Academy artists activists," Isaacs told some 160 Oscar nominees attending the annual affair in Beverly Hills. She was referring to artists expected to miss this year's Academy Awards as a result of President Donald Trump's controversial executive order temporarily banning citizens of seven Muslim-majority countries from entering the United States. A federal court has suspended the decree, for now. "There is a struggle today over artistic freedom that feels more urgent than at any time since the 1950s," Isaacs said to loud applause. "We stand up in support of artists around the world, we stand up to those who would try and limit our freedom of expression and we stand up for this fundamental principle: That all creative artists around the world are connected by that unbreakable bond and more powerful than nationality and politics. "And just as our work does not stop at borders, borders cannot be allowed to stop any of us." Among artists affected by Trump's travel ban are Oscar-winning Iranian director Ashghar Farhadi, nominated for best foreign language film for "The Salesman." Also set to miss the upcoming Oscars ceremony later this month are the subjects of "The White Helmets," a documentary about the volunteers who rescue victims in war-torn Syria. Among the stars mingling at the casual affair on Tuesday were Ryan Gosling and Emma Stone, whose romantic musical "La La Land" is expected to sweep the board at the Oscars after waltzing off with top honors at the Golden Globes as well as the Producers Guild and the Directors Guild awards. French actress Isabelle Huppert, nominated for best actress for rape-revenge thriller "Elle," received raucous applause as she stepped up for a class photo with fellow nominees, as did Viggo Mortensen, nominated for best actor for "Captain Fantastic" and Viola Davis, nominated for best supporting actress for "Fences." Show producers Michael De Luca and Jennifer Todd urged the nominees to keep their speeches short and concise should they take home a golden statuette on awards night. They presented a short film starring Kate McKinnon as 1930s fictional film star Gloria Concave offering hilarious tips on the dos and don'ts on the big night. The 89th Academy Awards will be held on Feb. 26 in Los Angeles.