"The whole concept is we are not going to let London Bridge, or any bridge, fall down," she was quoted as saying by the Press Association.
Londoner Elida Ercolano was visibly emotional after receiving her rose. "I think it's lovely, it's what London is actually about as a city," she said.
"It's what people should remember despite what's gone on. It's a great symbol and if nothing else it's bringing people together," Ms Ercolano said.
"It's very easy to believe the fear but boil it down and we are actually, in the main, good people and we should remember that," she added.
June Collis, from Gillingham, Dorset, said it was "beautiful and lovely to see the Muslim group come out and share their love against all the horrible things that have happened".
Muslim groups across the country have condemned the horrific terror attacks. Over 130 imams and Muslim religious leaders in the UK last week refused to perform the traditional Islamic funeral prayer for the London Bridge attackers, saying their "indefensible actions" were completely at odds with the teachings of Islam.
David Hackett, who is visiting the capital from Durham, said he found the event "very touching". "It's great to see people giving such a beautiful thing to demonstrate the love people have for each other," he said.
Nancy Cannata, from Massachusetts in the US, said, "It's very nice to see. And I think it's nice that they're Muslims -- it's not everybody in the Muslim community carrying out these attacks. There are good and bad people in every religion, and I wish people could realise that."