A Texan teenager arrested after a home-made clock he brought to school was mistaken for a bomb has capped a whirlwind month with a visit to the White House and a chat with President Barack Obama.

Ahmed Mohamed received a personal invitation from Mr Obama for Astronomy Night, an event the president uses to encourage young people to pursue careers in science, technology, engineering and mathematics. The two met and talked briefly.

Ahmed, 14, said he was grateful for the president's support and said he was fine with the "clock kid" nickname so many have given him over the past few weeks.

He said the lesson of his experience was: "Don't judge a person by the way they look. Always judge them by their heart."

The teenager brought the clock to at MacArthur High School in Irving last month to show a teacher, but another teacher thought it could be a bomb. The school contacted police, who ultimately chose not to charge Ahmed with having a hoax bomb, though he was suspended from school for three days.