Foster, the British architect whose firm is behind iconic buildings like the Gherkin in London, sent the following statement to Dezeen:
"I am devastated by the news of the loss of Zaha Hadid and cannot comprehend the enormity of her passing away. I became very close to her as a friend and colleague in parallel with my deep respect for her as an architect of immense stature and global significance."
"She was one of the very few architects as friends who was invited to my 80th birthday party in London last year. By a strange coincidence some days ago I received an email from one of her clients – someone she had designed a home for. With great pride he sent me about 20 pairs of images. Each pair showed the visualisation that Zaha presented and the reality as finally built. It was a beautiful juxtaposition of what Zaha promised and what she delivered. I was so looking forward to sharing with her these intimate insights. Tragically that will never happen."
"I think it was Zaha's triumph to go beyond the beautiful graphic visions of her sculptural approach to architecture into reality that so upset some of her critics. She was an individual of great courage, conviction and tenacity. It is rare to find these qualities tied to a free creative spirit. That is why her loss is so profound and her example so inspirational. And, besides, she was my dear friend."
Foster and Hadid were part of a small group of internationally famous London-based architects, which also included Richard Rogers.
In 2014, Foster and Hadid's firms were both chosen to design high-rise hotels in China for Jumeirah Group.