Tanzanians welcome U.S. President Barack Obama on Monday amid much fanfare.br br Arriving with his family, Obama will later host talks his Tanzanian counterpart Jakaya Kikwete.br br It's the last stop on his three-nation Africa trip, slated to boost ties with fast-growing African nations amid heavy competition from China.br br Looking to regain ground, Washington plans a $7 billion initiative to tackle Africa's lack of electrical power, with Obama also due to announce new trade projects.br br Streets were closed off and businesses shut in the commercial capital Dar es Salaam as part of security measures, much to the annoyance of some residents.