WASHINGTON >> In a fresh swipe at Iran, President Barack Obama has ordered new sanctions on the Islamic republic, including its Central Bank, moving to enforce a law he signed in December.

In a letter to Congress today, Obama said more sanctions are warranted “particularly in light of the deceptive practices of the Central Bank of Iran and other Iranian banks.” He said the problems included the hiding transactions of sanctioned parties, the deficiencies of Iran’s anti-money laundering regime and the unacceptably high risk posed to the entire international financial system posed by Iran’s activities.

The Central Bank sanctions were included as an amendment in the wide-ranging defense bill Obama signed into law at the end of 2011. The White House said Obama signed the executive order approving the sanctions on Sunday.

The new measures come as the White House tries to both ratchet up pressure on Tehran to abandon its nuclear program and dissuade Israel from launching a unilateral strike on Iran, a move that could roil the Middle East and jolt the global economy.

Obama said Sunday that he does not believe Israel has yet decided whether to attack Iran. The president said he still believes a diplomatic solution is possible.

Iran insists its nuclear pursuit is for peaceful purposes, but the West accuses Iran of developing the know-how to build a nuclear bomb. Defense Secretary Leon Panetta last week would not dispute a report that he believes Israel may attack Iran this spring in an attempt to set back the Islamic republic’s nuclear program.

In recent weeks, both the U.S. and European Union have imposed harsher sanctions on Iran’s oil sector, the lifeblood of its economy.

In Washington, the Senate Banking Committee easily approved yet more penalties on Tehran last week. The sweeping measure, which is not yet law, would target Iran’s Revolutionary Guard Corps, require companies that trade on the U.S. stock exchanges to disclose any Iran-related business to the Securities and Exchange Commission, and expand penalties for energy and uranium mining joint ventures with Tehran.