London, Oct 23 (IANS) Britain can lead the way in efforts to address the plight of children caught up in the Syrian conflict, actress Carey Mulligan has said.

The Great Gatsby star joined the demonstration just opposite the gates to Downing Street, where teddy bears were later laid in a poignant message from campaigners about the human cost of the long-running conflict on Saturday.

A small light brown-coloured teddy belonging to her one-year-old daughter Evelyn was amongst the pile, and she told how becoming a parent has motivated her to raise awareness and to help.

She said: "I brought one of my daughter's teddy bears here today and ever since having my child -- I've worked with War Child for a couple of years now -- but since having my daughter, it just drives home even more how unimaginable it would be for her to be in any of these situations and to have to deal with any of this."

"It just really drives me to speak out and do more if I can."

She described the demonstration as the opportunity to "stand up and say that we need to do something real".

Mulligan, an ambassador for War Child, has previously spoken out saying that the inaction in Calais -- where many unaccompanied refugee children have become stranded in the so-called Jungle camp -- made her ashamed to be British. But she said the arrival of young refugees in Croydon in recent days helped restore some of her faith.

She added: "I feel very proud to be British in this regard. We have made a strong stance this week."

"I think we really can lead the way here and we can lead people and work with our international allies to come up with a robust plan to finally put this to an end," the Independent quoted her as saying.

She recalled the night-time ritual of putting her daughter to bed and told the gathered crowd: "I'm safe in the knowledge that when I put Evie down to bed she is safe."

She added: "The parents in Aleppo aren't. They don't know what the night will bring."

As well as the protest, a letter was delivered to Number 10 demanding Theresa May take action to help end the violence.

It comes after the Prime Minister on Friday insisted the EU must keep "all options" open if Russia continues to commit atrocities in the conflict zone.