US President Joe Biden called a deadly mass shooting at a Texas elementary school "another massacre" and said it is time to act against future carnage. 

"I had hoped, when I became president, I would not have to do this, again. Another massacre. Uvalde, Texas. An elementary school. Beautiful, innocent, second, third, fourth graders," Biden said late Tuesday in an emotional address at the White House after returning from a trip to Asia.

"To lose a child is like having a piece of your soul ripped away. There's a hollowness in your chest. You feel like you're being sucked into it," he added.

The shooting at Robb Elementary School in Uvalde, Texas, about 83 miles (133 kilometers) west of San Antonio, left 18 students and one teacher dead.

The shooter was identified as Salvador Romas, 18, from Uvalde and was shot and killed by police who exchanged gunfire.

The president said these kinds of mass shootings rarely happen elsewhere in the world, adding that those with mental problems or those "who were lost" exist in other nations.

"But these kinds of mass shootings never happen at the kind of frequency that they happen in America. Why? Why are we willing to live with carnage? Why do we keep letting this happen?" said Biden.

"Where in God’s name is our backbone to have the courage to deal with it? It’s time to turn this pain into action," said the president, calling for standing up to the gun lobby.

"It's time for those who obstruct and delay or block the common sense gun laws -- we need to let you know that we will not forget. We can do so much more, we have to do more," he added./aa