Roseta, who was elected to the assembly last year as a candidate of the movement Citizens for Lisbon, said that she would step down at the end of October.

"I'm going to change my life,” she said at an event organised by the movement that she launched 12 years ago. “I'm going to turn 72; I find that a good age to change my life. I don’t know how many years I will live and so now those I have left have to be lived very intensely.

"I need time to do the things I want to do still in life and politics and this requires me to make these decisions," she went on, stressing that she would take advantage of her departure to work with teams researching in the field of housing.

Roseta stressed that while she is retiring from political positions, she is not bowing out of either life or politics. She took the opportunity to criticise Lisbon city council, particularly where the participation of citizens and in the field of urban policy is concerned.

Asked who might succeed her as president of the assembly, which she has overseen since 2013, Roseta said that this was not yet defined.

Roseta left the Socialist Party, of which she had been a member since 1987, to launch the Citizens for Lisbon movement in the run up to the 2007 local elections. That year it saw two candidates elected, including Roseta, who was re-elected in 2009.

In the wake of those elections, the movement signed an agreement with the governing Socialists that was key to its securing a majority in the assembly.

Roseta subsequently oversaw the country’s first local housing programme, which was approved by the assembly in 2010, and was responsible for the sector from 2009 to 2013.

In 2011, she also launched the BIP/ZIP programme to develop neighbourhoods and priority intervention zones, which was in 2013 awarded a prize for good practice in citizen participation by the International Observatory of Democracy.

In 2013, the Citizens for Lisbon movement renewed its agreement with the Socialists and Roseta was elected as a councillor and as president of the Municipal Assembly. In 2017 she was re-elected.

Roseta has also undertaken housing-related work in Portugal’s parliament, where she was elected as an independent in the Socialist list of candidates in 2015. In 2016 she proposed the creation of a working group on housing, urban rehabilitation and city policies, and coordinated the group until 2018.

That year she drafted and tabled with the support of the Socialist parliamentary group Portugal’s first basic legislation for housing, which has been in force since 1 October.

Roseta resigned as coordinator of the group in November last year after a political disagreement with the Socialist Party over the drafting of the legislative package on housing and opted not to stand as a candidate on the party’s list for this months’ legislative election.

In the 1960s Roseta was a leader of the student movement against the Salazar dictatorship and in 1973 she was detained by the PIDE, the secret police, at a time when she was secretary-general of the then National Union of Architects and presented a thesis on the subject of housing.

In 1975 she was elected as a member of the Constituent Assembly and was a candidate for the Social Democratic Party in elections up to 1982 and then, from 1987, for the Socialist party.

Roseta was also president of Portugal’s Order of Architects between 2001 and 2007.