City Hall has stepped into the Brexit debate by urging London mayor Sadiq Khan to protect the rights of the capital's EU citizens.
Khan attends regular meetings with Brexit secretary David Davis, and the London Assembly has been working to inform discussions by passing on the views of Londoners to the mayor.
In a letter to the Mayor, seen by City A.M., the chair of the London Assembly's Brexit working group Len Duvall said there was "high anxiety" among EU citizens.
At an open meeting in City Hall, Londoners from EU countries said there was still too much uncertainty about their future.
The government first outlined its proposals to EU citizens in June, saying there would be a range of statuses EU nationals would have to apply for.
Londoners told City Hall representatives they feared the changes would create an "administrative cataclysm" for those affected.
Duvall wrote: "Two main problems were identified: the uncertainty that may be created; and the administrative burden that the process poses, both for applicants and for those responsible for the processing of applications."
Duvall said Khan should demand a simpler system, and must alert the Brexit secretary to the risks of banks turning down mortgage applications from EU citizens.
The London Assembly is also pushing for more power after Brexit. It wants devolution of the employment and skills budgets, and a new growth fund to replace the social and development funds currently provided by the EU.
Duvall praised Khan for his "London is Open" campaign, which has aimed to make sure EU citizens and people from across the world feel welcome in the capital. However, Londoners have reported a rise in hate crime which has continued since the referendum.
"We strongly urge you to show further leadership on this issue to ensure that EU nationals can continue to make London their home," Duvall said.