More than 30 representatives from faith groups across the borough met on February 13 to respond to last month's atrocities in the French capital, which left 17 victims dead.
Members of Buddhist, Christian, Hindu, Jewish, Muslim and Sikh groups discussed the importance of working together to prevent extremism in all its forms.
They stressed the need for faith groups and the council to engage with young people and address the threat of online radicalisation, as well as for different religions to respect each others' beliefs.
Zubair Awan, joint secretary of Hounslow Jamia Masjid, where the forum took place, said: "Freedom of speech and expression is an important and highly earned value of democratic societies and must be exercised with care and respect for others. Fanaticism, in any form including through pen or pistol, has no place in our communities."
The event at the mosque in Wellington Road South, Hounslow, was organised by Hounslow Friends of Faith, set up to foster relations between the borough's many religions.
The group's chairman Ajit Singh said: "Young people need to be engaged through action, not just dialogue. Faith bodies and the local authority have a crucial role to tackle the issue of engaging with young people.
"We need to give them the tools to develop into law abiding citizens as equals. We must be careful of the language we use to each other, but also challenge it if necessary."
Islamist gunmen shot dead 12 people at the offices of the French satirical magazine, Charlie Hebdo, apparently in revenge for it printing cartoons of the Prophet Muhammad, on January 7. Another five people were killed by terrorists over the next two days.