SNP leader Nicola Sturgeon will address thousands of anti-nuclear protesters today at a demonstration calling for the scrapping of Trident.
Protesters will march through Glasgow city centre ahead of speeches by the SNP leader and Patrick Harvie, of the Scottish Greens, at a gathering in George Square.
The annual rally organised by the Scrap Trident group will be followed on April 13 by a blockade of Faslane naval base, home of the UK's nuclear deterrent.
Ms Sturgeon is expected to say: "Never before have the establishment Westminster parties been so unpopular - and never has there been a greater opportunity to build a progressive alliance across these islands to chart a different course.
"And nothing sets these two visions apart more than the nuclear weapons sitting just a few miles down the river Clyde.
"I give you my cast-iron assurance SNP MPs will never support Trident - and that is why we need as many SNP MPs as possible in the House of Commons.
"Future generations will never forgive us if we make the wrong choice."We must all of us seize the moment - vote to scrap Trident, vote for peace and vote for a progressive future."
Greens co-convenor Mr Harvie said the "Bairns Not Bombs" event will send a strong message to MPs elected in May to vote against renewal.
He said: "We have a chance to send a strong message that by re-purposing our military and adapting to the threats of the 21st century we can leave the Cold War mentality behind and free up funds to create the jobs our society needs."
Also addressing the gathering will be Labour's North Ayrshire candidate Katy Clark, Cat Boyd, from the Radical Independence Campaign, and Ann Henderson, of the STUC.
Organisers say they are expecting a good turnout with just over a month to go until the General Election.