PARIS (AP) — Activists worldwide gathered for May Day rallies and street protests Friday, calling for peace, higher wages and better working conditions as many workers grapple with rising energy costs and shrinking purchasing power tied to the Iran war.

May 1 is a public holiday in many countries to mark International Workers' Day, or Labor Day, when workers' unions traditionally rally around wages, pensions, inequality and broader political issues. Demonstrations were being held from Seoul, Sydney and Jakarta to many European capitals and cities across the United States.

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"Working people refuse to pay the price for Donald Trump's war in the Middle East," the European Trade Union Confederation, which represents 93 trade union organizations in 41 European countries, said. "Today's rallies show working people will not stand by and see their jobs and living standards destroyed."

In the United States, activists opposing President Donald Trump's policies are planning marches and boycotts.

Here's what to know about May Day.

Rising energy prices and living costs

Rising living costs linked to the conflict in the Middle East emerged as a key theme in Friday's rallies.

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In the Philippines' capital of Manila, large crowds marched to call for higher wages and lower taxes as protesters denounced the United States' role in the Iran war. Some held banners reading "no troops, no bases, no war games, resist U.S.-led wars." Protesters clashed with police blocking the way near the U.S. Embassy.

"Every Filipino worker now is aware that the situation here is deeply connected to the global crisis," said Josua Mata, leader of SENTRO umbrella group of labor federations.

In Indonesia, President Prabowo Subianto joined a May Day rally in the capital, Jakarta, greeting tens of thousands of people amid a tight police and military presence. Workers called for stronger government protection amid rising prices and difficulties in finding raw materials for their industry.

In Pakistan, May Day is a public holiday marked by rallies, but many daily wage earners cannot afford to take time off.

"How will I bring vegetables and other necessities home if I don't work?" said Mohammad Maskeen, a 55-year-old construction worker near Islamabad.

Rising oil prices have fueled inflation, which the government estimates at about 16%, in a country heavily reliant on financial support from the International Monetary Fund and allied nations.

Demonstrations across the world

In Istanbul, police detained some 15 protesters who tried to reach Taksim Square, the epicenter of landmark 2013 protests, in defiance of a government ban.

Turkey's government has long declared the square off-limits for demonstrations on security grounds, but some political parties and trade unions have vowed to march there.

In France, unions called for demonstrations in Paris and elsewhere under the slogan "bread, peace and freedom," linking workers' daily concerns to conflicts in Ukraine and the Middle East.

In Italy, the government approved nearly 1 billion euros ($1.17 billion) in job incentives this week, aiming to promote stable employment and curb labor abuses ahead of May Day. The measures extend tax breaks to encourage hiring young people and disadvantaged women, and seek to address exploitation tied to platform-based work. Opposition parties dismissed the package as "pure propaganda."

In Portugal, proposed labor law changes by the center-right government sparked a general strike and street protests last year. There is still no deal after nine months of negotiations with unions and employers. Unions say the proposals would weaken workers' rights, including by expanding overtime limits and reducing some benefits.

France's mandatory day off

May Day carries special meaning this year in France after a heated debate about whether employees should be allowed to work on the country's most protected public holiday — the only day when most employees have a mandatory paid day off.

Almost all businesses, shops and malls are closed, and only essential sectors such as hospitals, transport and hotels are exempt.

A recent parliamentary proposal to expand work on the day prompted major outcry from unions and left-leaning politicians.

"Don't touch May Day," workers' unions said in a joint statement.

Faced with the controversy, the government this week introduced a bill meant to expand May Day work to people staffing bakeries and florists. It is customary in France to give lily of the valley flowers on May Day as a symbol of good luck.

"May 1 is not just any day," Small and Medium-sized Businesses Minister Serge Papin said. "It symbolizes social gains stemming from a century of building social rules that have led to the labor code we know in France. It is indeed a special day."

Calls for street protests and boycotts in the U.S.

Activists and labor unions are organizing street protests and boycotts across the United States, where May Day is not a federal holiday.

May Day Strong, a coalition of activist groups and labor unions, has called on people to protest under the banner of "workers over billionaires."

Voicing strong opposition to Trump's policies, organizers listed thousands of May Day actions across the country and are seeking an economic blackout through "no school, no work, no shopping."

Demands include taxing the rich and putting an end to the Trump administration's immigration crackdown,

While labor and immigrant rights are historically intertwined, the focus of May Day rallies in the U.S. shifted to immigration in 2006. That's when roughly 1 million people, including nearly half a million in Chicago alone, took to the streets to protest federal legislation that would've made living in the U.S. without legal permission a felony.

Roots in Chicago

May Day, or International Workers' Day, traces back more than a century to a pivotal period in U.S. labor history.

In the 1880s, unions pushed for an eight-hour workday through strikes and demonstrations. In May 1886, a Chicago rally turned deadly when a bomb exploded and police responded with gunfire. Several labor activists — most of them immigrants — were convicted of conspiracy and other charges; four were executed.

Unions later designated May 1 to honor workers. A monument in Chicago's Haymarket Square commemorates them with the inscription: "Dedicated to all workers of the world."

AP journalists Barry Hatton in Lisbon, Portugal, Giada Zampano in Rome, Munir Ahmed in Islamabad, Niniek Karmini in Jakarta, Indonesia, and Jim Gomez in Manila, Philippines, contributed to this story.