President Donald Trump has said US cities should be “sanctuaries” for Americans not for criminal “aliens”, a week after a US court acquitted a Mexican immigrant accused of fatally shooting an American woman.

On July 1, 2015, 32-year-old Kathryn Steinle, while walking with her father and a friend was shot by Mexican national Jose Inez Garcia Zarate in the Embarcadero district of San Francisco.

The shot ricocheted off the concrete deck of a pier striking the victim in the back. Steinle died two hours later in the hospital as a result of her injuries.

The shooting elicited controversy and political debate over San Francisco’s status as a sanctuary city, as Zarate was a Mexican national who was unlawfully residing in the US.

Trump has highlighted the case as an example of the failure of “sanctuary cities”, where local officials did not work with authorities to enforce immigration laws.

Asserting that no American should be separated from their loved ones because of preventable crime committed by those illegally in the country, Trump said that cities should be sanctuaries for Americans not for criminal aliens.

“No American should be separated from their loved ones because of preventable crime committed by those illegally in our country. Our cities should be Sanctuaries for Americans not for criminal aliens,” Trump said in his weekly address to the nation.

Last week, in a “final injustice”, Kate’s killer was acquitted on all of the most serious charges, he said.

This he said is one more reason Americans are so upset by sanctuary cities and politicians who shield “criminal aliens” from federal law enforcement and all of the problems involved with the whole concept of a sanctuary city.

“They are no good. We mourn for all of the American families, of all backgrounds, who will have any empty seat at Christmas this year because our immigration laws were not enforced,” Trump said.

“Unfortunately, Democrats in Congress not only oppose our efforts to stop illegal immigration and crack down on sanctuary cities now they are demanding amnesty as a condition for funding the government, holding troop funding hostage and putting our national security at risk. We cannot allow it,” he said.

Trump said every Senator and Congressman will have to make a choice: do they want to protect American citizens or do they want to protect “criminal aliens”.

In his address, Trump said Steinle’s death is a tragedy that was entirely preventable.

“She was shot by an illegal alien and a 7-time convicted felon who had been deported five times but he was free to harm an innocent American because our leaders refused to protect our border, and because San Francisco is a sanctuary city,” he said.

“In sanctuary states and cities, innocent Americans are at the mercy of criminal aliens because state and local officials defy federal authorities and obstruct the enforcement of our immigration laws,” Trump said.