Shadow chancellor John McDonnell is set to warn the global elites gathered at Davos there will be "a price to pay" if they stand in the way of change to the international economic system.
Attending the Swiss ski resort's World Economic Forum for the first time, Mr McDonnell will warn that the super-rich face "a political and social avalanche" unless the demands of ordinary people are met.
Speaking ahead of his trip, Mr McDonnell said he would use a speech on Friday to demand a global drive against tax-dodging and financial secrecy, as well as democratic control over the economy.
"I am going to Davos with a warning for the global elite," the shadow chancellor said.
"The Davos few have hoarded power and wealth and failed the many. If they stand in the way of the change that's needed, they risk raising the price they pay. Change is coming either way."
Mr McDonnell appears on the speakers' list for the week-long event alongside world leaders including Donald Trump, Angela Merkel, Emmanuel Macron and Theresa May.
Answering questions in the House of Commons shortly before leaving for Switzerland, Mrs May joked, "who knows, I might even bump into the shadow chancellor while I'm there".
Mrs May was due to hold talks with Swiss president Alain Berset on Wednesday and meet Mr Trump on Thursday.
Mr McDonnell said many of those attending Davos were "patting themselves on the back" over the return of growth a decade after the financial crisis of 2007/08.
But he said: "They should be worried. In the real world, outside the Davos bubble of Alpine restaurants and chalets, the global economic system they have built isn't working for billions of people.
"And just as Davos faces the risk of an avalanche this week, growth for a few risks a political and social avalanche unless there is fundamental change to our rigged economic system."
Ordinary people, who for years have had to focus merely on "getting by", were now starting to demand "real change", Mr McDonnell said.
"In country after country people have suffered a decade of austerity since the crash of 2008," he said.
"They know austerity was a con trick when they see that the wealth of the super-rich has doubled and banks and corporations have been rewarded with tax cuts."
Voters who have had to accept low wages, long hours and public service cuts as the price of austerity have watched the rich enjoy soaring pay and bonuses while dodging tax "on an industrial scale", Mr McDonnell said.
And he added: "My warning is this. If the current system isn't radically changed and its rules rewritten, people are not going to put up with it.
"Real change to the system is Labour's mission, one we share with parties and movements all over the world.
"The real wealth creators - that means all of us, not just those with offshore bank accounts - must share in the prosperity we all create."
A senior Labour source said leader Jeremy Corbyn had turned down an invitation to Davos.
"Davos has become representative of a system and a set of global elites which have failed," the source said.
"It is clearly a broken system that isn't delivering for people.
"That doesn't mean it is not worthwhile for Labour politicians to go there.
"Jeremy won't be going, but John McDonnell will."
The source said Mr McDonnell would make clear to representatives of the global elite that they needed to be "held to account" for growing inequalities, stagnating incomes and the fact that growth had been slower than it was before the era of neo-liberal economics.