The US President Barack Obama has begun a week-long campaign to revive America's economy, exactly eight weeks before Congressional elections. In a speech to workers, Mr Obama announced plans to invest 50 billion dollars in the country's transport system. Speaking to workers, he said, tens of thousands of kilometers of highway would be rebuilt, railway links will be improved and airports and air traffic control systems upgraded. He said this will create jobs and leave a lasting legacy. Tomorrow, Mr Obama is expected to launch permanent tax breaks for companies that invest in research. The Opposition Republicans have criticized the plan as ineffective and the one that will increase already excessive federal spending.