The US administration is under pressure to launch the second full-scale review this year of the acquisition of US assets by an Asian company - a sign of rising concern in Washington that Asia's growing economic power may threaten US security.According to a report on the website of Financial Times, three Republican senators this week urged John Snow, US treasury secretary, to review the $130 million purchase of Tyco International's underwater cable network by the Tata group firm Videsh Sanchar Nigam (VSNL).