Beyonce was on her "King B" game Friday (August 10), while shooting the music video for “I Was Here” at the United Nations General Assembly Hall in New York City. Rocking a beautiful white March Bouwer gown, Beyonce performed a powerful and touching live rendition of the ballad, which is lifted from her latest album '4.'

“WOW WOW WOW!!!!!!! Beyonce killed it at the UN!!!” songwriter Diane Warren tweets. “Tonite was one of the best experiences ever.”

Anderson Cooper, who interviewed Beyonce for CNN's “Anderson Cooper 360? and for his daytime talk show “Anderson Live,” was also hypnotized by B's performance. “Wow, @Beyonce just performed in the UN General Assembly. She was awesome,” he adds.

As Singersroom previously reported, the R&B superstar teamed with The United Nations and humanitarian aid organizations for a global campaign, which aims to shine light on humanitarian work and encourage people around the world to get involved by doing something good for others.The visuals, which will be donated to the campaign by Beyonce and songwriter Diane Warren, will be released on August 19.

"We all see the headlines and we think what can I really do to help?", Beyoncé previously stated. "World Humanitarian Day is an opportunity for all of us to work together to make a difference. This is our time to leave our mark on the world and show that we were here and we care."

World Humanitarian Day is a global day to celebrate humanity and the spirit of people helping people. Communities and organizations across the globe will celebrate World Humanitarian Day through commemorations and public events, from Dubai to Geneva, Bangkok to Panama City and Addis Ababa to New York.

For more details, visit the newly launched website at www.whd-iwashere.org.

Photo credit: Cliff Watts

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