Protesters in Lisbon surround parliament

LISBON (Reuters) - About 40,000 people marched in Portugal on Saturday as part of a global day of protest against the financial elite and hundreds broke through a police cordon around the parliament in Lisbon to occupy its broad marble staircase.

It was one of the biggest turn-outs in any country and followed the center-right government's announcement on Thursday of a new batch of austerity measures.

More than 20,000 people marched in Lisbon from central Marques de Pombal square to surround the Sao Bento Palace housing the National Assembly.

"This debt is not ours!" and "IMF, get out of here now!", they chanted.

Banners read: "We are not merchandise in bankers' hands!" or "No more rescue loans for banks!".

A group of youths broke into the parliament shouting "Invasion, invasion!" Riot police brought the situation under control without any more violence than some pushing and shoving.

About 20,000 people also rallied in Oporto, Portugal's second city.

The austerity measures included pay cuts in the public sector, which infuriated workers across the country. Debt-ridden Portugal had to impose tough tax hikes and spending cuts to meet its fiscal goals set under a 78-billion-euro ($108.2 billion) EU/IMF bailout.

"We are sick of always being the ones who pay the bill in this crisis. It's never the banks, it's always the people," said 46-year-old construction worker Antonio Rui.

"There is no lack of reasons for people to take to the streets and there's a lot more people here today than we expected," said Joao Labrincha, one of the organizers of the rally and coordinator of the "Precarious Generation" movement.

"The prime minister just showed that he had lied when he promised that taxes would not rise and that holiday bonuses would not be cut. People feel betrayed by that," he said.

The country's two main unions will meet on Monday to discuss future labor action to protest against the measures, and could call a general strike. Protests have been peaceful in Portugal so far and analysts generally do not expect the sort of violent strife as seen in Greece or Italy.

(Reporting By Andrei Khalip; Editing by Angus MacSwan)