US President Barack Obama has placed stricter sanctions on Iran's government, including its central bank, BBC News reported. In an executive order, Mr Obama said he was freezing all Iranian government assets held or traded in the US.
On Sunday, Mr Obama said the US and Israel were "in lockstep" in their policy towards Iran.
Concerns have grown in Israel and the West that Iran is developing nuclear weapons, although Tehran says its nuclear programme is entirely peaceful.
The new US sanctions include blocks on the Central Bank of Iran, imposed "in light of the deceptive practices" the bank to conceal transactions already banned by previous sanctions.
The curbs were also prompted by Iran's "deficient" efforts to combat money-laundering, the executive order said.
The US introduced new sanctions on Iran at the end of 2011 but stopped short of targeting the central bank.
But the latest round of sanctions gives American institutions the powers to freeze assets related to the Central Bank of Iran, instead of just turning them back.
In a statement, the US Treasury department said the order was part of "the administration's resolve to hold the Iranian regime accountable for its failure to meet its international obligations".
Iran "will face ever-increasing economic and diplomatic pressure" until it answers the international community's "well-founded and well-documented concerns" about its nuclear programme, the Treasury said.
/
BBC/