Missouri tornado: Obama to visit after Europe tour
US President Barack Obama says he will visit the tornado-hit state of Missouri on Sunday, straight after returning from a six-day tour of Europe.
Sunday's huge tornado cut a path some six miles (10km) long and at least half a mile wide through the city of Joplin, killing at least 116 people.
President Obama said the tornado was "devastating and heartbreaking".
He vowed the US government would "do absolutely everything we can" to help victims recover and rebuild.
Meanwhile, the US National Weather Service warned of more storms on Tuesday, with the risk for severe weather increasing later in the day.
South-east Kansas and Missouri are set to be battered by 70mph winds, hail "the size of baseballs" and possible tornadoes, said the agency.
Reduced to rubble
Mr Obama was speaking from London before meeting Queen Elizabeth II at the beginning of his stay in the UK.
It is the second stop on a four-country tour of Europe, and Mr Obama is due back in Washington on Saturday night.
"I want everybody in Joplin, everybody in Missouri, everybody in Minnesota, everybody across the Midwest to know that we are here for you," said Mr Obama.
"The American people are by your side. We're going to stay there until every home is repaired, until every neighbourhood is rebuilt, until every business is back on its feet."
The damage wrought in Missouri could, Mr Obama said, end up exceeding the destruction of Tuscaloosa, Alabama, by tornadoes in April.
Federal disaster and homeland security officials have travelled to the affected areas, said the US president.
Much of the south side of Joplin is reported to have been levelled, with churches, schools, businesses and homes reduced to rubble.
On Monday, Missouri Governor Jay Nixon said storms had caused extensive damage across the state.
"As a state, we are deploying every agency and resource available to keep Missouri families safe, search for the missing, provide emergency medical care, and begin to recover," he said.
He warned that the storms were not finished and urged Missourians to keep a close eye on the latest weather information.