The government has written to the Reserve Bank of India (RBI) over supervisory lapses in Punjab National Bank scam. <br/><br/>Highly placed sources in the Finance Ministry said the government has asked RBI to check efficiency of systems to detect frauds.<br/><br/>Meanwhile, a meeting was held today between officials of Central Vigilance Commission, RBI and Punjab National Bank in New Delhi in the backdrop of the case.<br/><br/>