Oprah Winfrey has just announced she will donate $500,000 (£358,000) to the March For Our Lives event, which is being held to call for an end to gun violence after 17 students were killed in the shooting at Marjory Stoneman Douglas High School in Parkland, Florida.
Winfrey's generous donation comes after George and Amal Clooney revealed they would march with students on 24 March and donate $500,000 in the name of their children Ella and Alexander to help pay for the event.
In a tweet posted last night, the television host (and potential 2020 presidential candidate) said she would be matching the Clooney's donation.
'These inspiring young people remind me of the Freedom Riders of the 60s who also said we've had ENOUGH and our voices will be heard,' Winfrey concluded her post.
March For Our Lives was formed by survivors of the shooting and will hold a rally in Washington, 'to demand that a comprehensive and effective bill be immediately brought before Congress to address...gun issues,' according to the organisation's mission statement.
In a statement, Clooney said: 'Our family will be there on March 24 to stand side by side with this incredible generation of young people from all over the country, and in the name of our children Ella and Alexander, we're donating 500,000 dollars to help pay for this groundbreaking event. Our children's lives depend on it.'
Later on Tuesday, director Steven Spielberg and wife Kate Capshaw said they'd also match the Clooneys' donation.
In an emailed statement, they said: 'The young students in Florida and now across the country are already demonstrating their leadership with a confidence and maturity that belies their ages.'
Over the weekend, dozens of students organised a 'lie-in' protest outside the White House in Washington calling for gun reform.
At a gun-control rally in Fort Lauderdale, Florida, Stoneman senior Emma Gonzalez also delivered an impassioned speech, in which she criticised the country's lax gun laws, the National Rifle Association (NRA), and politicians who profit from the organisation.
'The guns have changed, but our laws have not,' Gonzalez said. 'We certainly do not understand why it should be harder to make plans with friends on weekends than to buy an automatic or semi-automatic weapon.'
Yesterday, 100 high school students boarded buses to Tallahassee to try and encourage lawmakers to change gun laws.
The Women's March youth branch, EMPOWER, is also organising a national school walk out on 14 March, on the one month anniversary of the Florida shooting. CNN reports the rallies are scheduled to begin at 10am in every time zone across the US and last for 17 minutes — one for each victim who lost their life in the massacre.
Meanwhile, the White House says President Trump will host a listening session with high school students and teachers on Wednesday 21 February and meet with state local security officials on Thursday.