Government backed investment firm 1Malaysia Development Berhad (1MDB) could become 1 Malaysia "debt of billions" instead if its financial performance continues, Anwar Ibrahim said today.

The opposition leader ( left ) claims that 1MDB has been steadily accumulating debt and if left unchecked, the company, a brainchild of Prime Minister Najib Abdul Razak, could start affecting the national financial situation.

"We are predicting that more debt needs to be undertaken by 1MDB in the future to fund mega projects like Tun Razak Exchange and Bandar Malaysia, which could cost RM45 billion," Anwar said.

"Everyone knows that in the current economic situation, it is only fair to take a cautious approach in spending."

Anwar, who is also PKR de facto leader, warned that 1MDB could become another "liability to the country” as acquiring more debts would leave the next generation inundated with debts.

He was referring to 1MDB's financial statement ending March 2013, which revealed that the company has RM42 billion in debts, far exceeding the RM8.4 billion debt it had the previous year.

Anwar also questioned the wisdom and reasoning behind 1MDB parking billions in funds at an offshore account in the Cayman Islands .

1MDB’s latest audited accounts revealed that the company has RM12.1 billion in overseas investments, including a sum of RM7.2 billion in the Cayman Islands which is available for sale.

"Who has control over these accounts? Why is the money not invested in Malaysia?" Anwar asked, noting that no answers had been forthcoming from the government so far.