Barack Obama has become the first US President to host a Twitter town hall meeting to reach out to weary Americans on a range of issues, including the state of the world's largest economy.

"I am going to make history here as the first President to live tweet," Obama, the 44th US President, said as he kicked off an event billed as a "Twitter Town Hall" from the East Room of the White House on Wednesday.

Obama used a live webcast to answer questions, submitted via tweets containing the hashtag #AskObama, on issues ranging from jobs to the economy.

"It's only 140 characters," moderator and Twitter's co- founder Jack Dorsey reminded Obama as he failed to keep his answers to 140 characters.

During his tweeting session, Obama did take 18 questions and gave feedback on six responses.

A panel of users re-tweeted questions to choose those to be asked.

Obama, who pioneered the use of social media during his 2008 election campaign, began the event by tweeting his own question: "In order to reduce the deficit, what costs would you cut and what investments would you keep?"

He then answered the question, saying the US must "make a determination in what programmes could help us grow", like programmes focused on clean air and water.

"It could cause a whole new spiral into a second recession or worse," Obama said of the potential effects of a failure to reduce the deficit.

Obama had previously said he wished to reduce the deficit by USD 4 trillion in the next decade by trimming domestic spending, including defence, and raising taxes on wealthy Americans.

Macon Phillips, the White House Director of Digital Strategy, said in a statement that the purpose of the Twitter town hall meeting is to "try to find new opportunities to connect with Americans around the country.