US Immigration and Customs Enforcement (ICE) on Sunday launched raids targeting undocumented migrants across the country, according to US officials.

US President Donald Trump described Sunday's planned action targeting families as a "major operation" covering several major cities, including Los Angeles, New York, Chicago and Houston.

Trump has repeatedly called on authorities to do more against illegal immigration and has made it one of his priorities as he steps up his campaign for reelection next year. But many officials in the targeted cities refused to cooperate.

Immigrants and aid workers around the country were on standby for the raids on Sunday, but there were only reports of a small number of small-scale operations in select cities.

Read more: 'Tough stuff': Mike Pence sees Donald Trump's US migrant camps

Protesters have gathered around the country to decry the raids

'Unsuccessful actions'

New York Mayor Bill de Blasio, who opposed cooperating with ICE, tweeted that the operation was not working as initially planned by the White House.

"Receiving reports of attempted but reportedly unsuccessful ICE enforcement actions in Sunset Park and Harlem," said de Blasio. "Remember: you have rights" he told the people involved.

Read more: Trump backs down on US census citizenship question

'Nothing new'

ICE's acting director, Matthew Albence, told The Associated Press that the operation "is nothing new."

"We are doing targeted enforcement actions against specific individuals who have had their day in immigration court and have been ordered removed by an immigration judge," he later told broadcaster Fox News when asked for an update.

Trump even retweeted his son, Donald Jr, on Saturday with the words "Does anyone else remember when Democrats used to oppose illegal immigration?" followed by a video of various Democrats, including former presidents Bill Clinton and Barack Obama, speaking of their opposition to illegal entry into the US.

Trump won the 2016 presidential election on a hard-line platform to tackle irregular migration. He has since enacted several controversial anti-immigration policies, including a so-called Muslim travel ban.

Read more: Building walls to keep climate refugees out

Every evening, DW's editors send out a selection of the day's hard news and quality feature journalism. You can sign up to receive it directly here.

ls,dr/se (AP, dpa)