It is in cities that new forms of poverty and new groups of people facing vulnerability, like the working poor, are first seen.

Global strategies such as the UN's Sustainable Development Goals (SDGs) or the EU's Pillar of Social Rights are powerful tools to address these challenges, but they will only succeed with the support of cities as active agents of social change.

Local authorities play a central role in delivering social inclusion and welfare measures, as front-line providers of public services, such as housing support.

Principle 19 of the EU social pillar, and goal 11 of the SDGs both acknowledge the right to affordable and good quality housing to be a fundamental right for those in need. As city leaders, however, we recognise that this does not go far enough. We need affordable housing for all people.

Cities doing more

In Barcelona we took action by developing the 'Cities for adequate housing' declaration adopted in New York.

So far, seven other cities in Europe and the Americas have signed this municipalist declaration and many more will follow.

As the closest level of government to citizens, we understand what people need and how to ensure cities are equitable and inclusive places to live.

We therefore call for more concerted action across all levels of government around five actions.

Firstly, as cities we need more powers to intervene in our local housing markets, especially to regulate the housing rental market, protecting tenants from speculative bubbles and also to ensure the right to homes for people living in the city.

Secondly, given that publicly-supported housing is an important resource for fighting housing poverty and social exclusion in cities, we are demanding more funds to invest in public housing at the local level.

Thirdly, in the interest of being able to provide adequate housing for as many people as possible, we encourage the use of national level subsidies and tax exemptions to foster public-private partnerships.

Fourthly, we recognise that these demands must go hand in hand with better urban planning, where housing contributes to better social mix and goals of social, economic and environmental sustainability.

Lastly, we want to enhance cooperation between cities and exchange of knowledge and best practice through networks such as Eurocities, which represents major European cities.

Action at all levels

Cities are committed to act on the principles of the EU social pillar and the SDGs, and Eurocities members are meeting in Stuttgart on October 23-24 to discuss how to link the two agendas.

However, to achieve shared goals to create a fairer, more sustainable society for all, we need to move the right to housing further up in the EU political agenda.

The Urban Agenda for the EU, which recognises the role of cities and the importance of bringing different levels of government together around the same table to discuss issues with an urban impact, is a good place to start.

The housing partnership, one of the 12 areas the Urban Agenda has been focussing on, has recommended actions for better knowledge, better policy and better funding for adequate housing for all.

We also need to ensure that cities keep the crucial support provided via the European Social Fund.

Evidence from the current programming period shows that when local authorities are involved in defining priorities for EU cohesion funding, results are stronger.

Linking these funds to the implementation of the EU social pillar at the local level and allowing flexibility to combine with other EU funding sources, would allow cities to better tackle social challenges like homelessness and gentrification in a holistic way.

Cities cannot solve these problems alone. We need the member states and the EU on board.

With other members of Eurocities, we have asked for a European Council recommendation to reinforce the right to affordable housing for all.

Without a strong recommendation to protect this right, access to affordable housing will remain a problem that will continue to increase the risk of poverty, exclusion and homelessness.

We need changes to EU and national legislation to make the right to adequate housing a reality for all people.

Cooperation must go two ways. Global goals must be made to work at the local level and accommodate local concerns. At the same time, cities should be included in decisions taken at all levels of government as equal partners.

Cities are the best allies for member states and the EU to build a more social Europe and a sustainable future for all.

Laia Ortiz is deputy mayor of Barcelona and chair of Eurocities Social Affairs Forum. Eurocities is the political platform for major European cities, with a network the local governments of over 140 of Europe's largest cities and more than 40 partner cities that between them govern some 130 million citizens across 39 countries.