Tackling air quality and fighting to reopen a women's unit in St George's Hospital are two key campaign priorities for the Green Party candidate in the Tooting by-election this June.

Esther Obiri-Darko, who stood in last year's general election, is hoping the lack of national picture in a by-election will help her chances as she seeks to become the new MP.

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She said: "It is really important to give people in Tooting an alternative choice to what is there at the moment.

"The wonderful thing about a by-election is that you are not voting for a party to form government, we have been living under that for a year.

"This is an opportunity for the people in Tooting to vote for the values that they have.

"I am putting a positive message out there for hope."

Ms Obiri-Darko said her priorities would be tackling air quality and the rental situation.

She said: "My priorities are fighting to reopen the urogynaecology unit in St George's, fighting to reverse the damage of privatisation as well as clean air.

"I think the biggest thing Londoners worry about is air quality.

"It is a big problem and thousands of deaths are caused by it. We need to be up in arms about it."

The Green Party candidate, who also stood for the Merton and Wandsworth seat in the Greater London Authority elections, supported the junior doctors strike, offering tea and biscuits on the picket line.

May 20: Full candidate list for Tooting by-election announced

Ms Obiri-Darko also said the rental market needed to be tackled as so many people cannot afford to buy their own homes.

She supports the Crossrail 2 station coming to Tooting Broadway rather than Balham even though this will impact house prices in Tooting.

She said: "Most of us are only two months away from having to move again at any point, that needs to be addressed in terms of fighting for a renters' bill.

"The majority of us will not afford our own homes and the same people will not if Crossrail 2 comes to Tooting anyway.

"There will be so many other positive knock-on effects."

Knife crime has become an issue in Tooting in recent years, and Ms Obiri-Darko said engagement with young people is the key to reducing it.

She said: "There are many issues that cause knife crime, it is not just one issue, housing, over-crowding in schools, social care issues, are part of it.

"You need to engage with young people, we need to go to them and make them feel that they are doing the politics."

The Tooting by-election will be held on June 16, with the count taking place the same night.