Hundreds of thousands of people are expected to "march for equality" in Washington DC on Saturday.

It's no coincidence that they are marching as Donald Trump spends his first day as American president.

While his supporters say he will "make America great again" others fear his plans.

Organisers estimate over 600 protests will also be held around the world, with 14 taking place in UK cities including Leeds, Cardiff and London.

The marches aren't all specifically anti-Trump: for example the London march is made up of those raising awareness about disability issues, domestic violence and the global refugee crisis, among other causes.

For some people this will be the first time they have taken to the streets to make a political statement.

We spoke to four London marchers who have never protested before now.

Alexandra: 'Marching is a way of showing others that they're not alone'

Alexandra Riccu, 20, grew up in Somerset and is now studying drama in London.

She hopes that joining her first march will offer comfort to what she sees as a rise in "fascism" in modern politics.

"I think there's a worrying trend towards bigotry in general in the world," Alexandra tells Newsbeat.

Donald Trump represents a growing trend that sexism is OK and that's not OK Flo Holland-Norris

She thinks it is "a way of showing others that they're not alone".

"Feeling isolated can cause people to do stupid or extreme things, but when you feel you've got backing behind you, you feel reassured."

And she has a specific message for President Trump:

"Don't take us too lightly," she says. "Don't ever try to grab us by the whats-its."

Flo: 'I have definitely seen young people become more open with their political views'

Flo Holland-Norris is a 20-year-old history and theology student from Chichester.

She works weekends and says this is the first time she's felt motivated enough to book time off to join a march.

She says she doesn't "see it as a march against Donald Trump" but what she thinks he represents.

"He represents a growing trend that sexism is OK and that's not OK," she says.

"Britain and the US are meant to be countries that other countries look to as beacons of equal rights."

She says she has seen her friends become more political and believes social media encourages young people to share their views publicly.

Hayley: 'I'm terrified about what will happen to women's rights and women's voices'

Although not all the London marchers are protesting about President Trump, Hayley Smith, 28, says she's "scared" about his time in office and the impact it will have on women.

"It's on such a huge scale around the world - it's something I want to be a part of," Hayley tells Newsbeat.

"I can't even imagine what it's like in America at the moment."

Hayley says social media has had a massive effect in encouraging young people to get involved but she thinks action on Twitter and Facebook is not enough.

"The world is going online but with this everyone's realising things need to come offline and everyone needs to unite and come together as human beings," she says.

Above all, she hopes Donald Trump will take notice of the women's marches across the world.

Josh: 'Men are allowed at this march and that is what it's all about - equality'

"It's only in the last year where I've become quite politically charged," says Josh McLean, 23, who will be marching as part of domestic violence campaign UK Says No More.

"It's time for me to do something about it, to show some support, get involved and take a stand.

"A lot of young people, for a lot of my friends, this march is really important to them.

"This is the first time we've had to go out, make a change and try to do something different."

He hopes the marches across the world send a clear message to Donald Trump.

"I want them to know it's not going to be easy for the people in power to do what they want to do," he says.

"Marches across the world, for one reason and one reason only, speak volumes. They're going to realise how many people are involved and invested in this issue."

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