The largest of Sunday's protests against US President Donald Trump took place in the capital, Mexico City, where thousands of people marched down a central avenue dressed in white and waving the nation's red, white and green flag.

"Mexico must be respected, Mr. Trump," a giant banner carried by demonstrators read.

Many others shouted "We want bridges, not walls," in reference to the billionaire president's plan to build a war on the US-Mexican border.

As well as Mexico City, rallies were well-attended in about 20 cities, including Guadalajara in the west of the country's interior.

The nationwide demonstrations have been backed by dozens of universities, business associations and civic organizations, which called on citizens to join forces to show their indignation at the new US leader.

"We're here to make Trump see and feel that an entire country, united, is rising up against him and his xenophobic, discriminatory and fascist stupidity," said Julieta Rosas, a literature student at the National Autonomous University of Mexico.

During his election campaign, the real estate magnate made several disparaging remarks about Mexican immigrants who live in the US, calling them "criminals" and "rapists."

Since he took office on January 20, Trump has vowed to press ahead with the border wall and raised the ire of Mexico's leaders further by saying that, one way or another, the US's neighbor to the south would pay for its construction.

Leaders' embarrassment

President Enrique Pena Nieto canceled a trip to Washington last month over Trump's insistence that Mexico will fund the wall.

Trump has also threatened Mexico's economy with by warning that he would terminate the country's privileged trade relationship with the US and blaming Mexico for the loss of American jobs.

Trump has promised to renegotiate the North American Free Trade Agreement and has vowed to slap steep tariffs on Mexican-made goods.

Mexico sends 80 percent of its exports to the US - nearly $300 billion in goods in 2015.

While Sunday's protests saw strong turnouts, opponents of Pena Nieto accused him of using the anti-Trump momentum to boost his own popularity, and refused to take part.

The hashtag "#It'sNotTrumpIt'sPena" is trending on Twitter in Mexico, amid support switching to Mexican presidential hopeful Andres Manuel Lopez Obrador, who is leading opinion polls.

Obrador is being billed a "leftist Donald Trump" because of his populist, anti-establishment rhetoric.

mm/jm (AFP, dpa)