Various Israeli sources and the pro-Israel lobby, the American Israel Public Affairs Committee (AIPAC), are also contributing to the efforts, particularly through specific legislation in various American states where pension funds hold stock in firms invested in Iran.
The economic sanctions against Iran are being pursued on a number of fronts simultaneously. On the international front, this effort is focused on the United Nations Security Council.
On the American domestic scene, several bills have recently been put before Congress. These bills would restrict U.S. cooperation with states and companies doing business with Iran.
Legislative proposals have also been put forth that would order pension funds to divest from firms with commercial links with Iran.
At the same time, the U.S. administration is working, mostly through the Treasury, on convincing banks throughout the world to make the transfer of funds related to Iran more difficult.
A senior U.S. Treasury official, Stuart Levey, has recently returned to Washington from a visit to the Middle East, which included a visit to Israel. His team has revealed that in coming months banks and credit companies may decide to freeze their ties with Iran after having been presented with data on the types of activities supported by the Iranian financial transactions.
The front on which there is a flurry of activity is the various American states and their local legislatures. In Ohio, for example, a bill was put forth last week, which would require the state to withdraw its investments from any company doing business with Iran. Similar bills are being prepared or are already in the legislative process in the local governments of many other states.
The two Ohio legislators behind the divestment bill, Josh Mandel and Shannon Jones, say billions of dollars in state residents' pension funds are invested in firms trading with countries supporting terrorism, including Iran.
The Ohio civil servants fund holds investments in 102 firms with commercial ties to Iran. The pension funds of Ohio school teachers has invested in 48 firms trading with Iran. The two Ohio state representatives would like for these investments to come to an end.
At an AIPAC conference held Monday in Washington, Executive Director Howard Core announced that the pro-Israel lobby will begin working with specific states in order to explore different ways of chocking investments necessary for Iran to develop nuclear weapons.
Official Israeli figures have briefed legislators in a number of states on this issue and the head of the opposition, Benjamin Netanyahu, is visiting Washington in an effort to convince the governors of various states to rally behind the economic boycott effort.
According to estimates, some 300 large international corporations are participating in serious investments in Iran. Experts say that focusing boycott efforts on them may cause serious economic difficulties to the regime in Tehran.
Dr. Matthew Levitt of the Washington Institute for Near East Policy, who worked on Levey's team at the Treasury, said Sunday that, "If the effort is focused on several dozen corporations, it will be sufficient," because this is the number of firms invested in Iranian petroleum, the critical area of that country's economy.
At the AIPAC conference, Levitt said that taking into consideration the limited diplomatic pressure that can be brought to bear on Iran, as well as the dangers and complexities of a potential military operation, the economic efforts of the administration are now the most efficient tool.
New York City Comptroller William Thompson Jr., whose responsibilities also include the city's pension plans worth several hundred million dollars, described his efforts to pinpoint corporations with investments in Iran, so city pension funds can divest from them.
Speaking at the AIPAC conference, he said the assumption is that many of these firms will prefer to cut their ties with Iran in order to preserve the investments of American institutions.
In recent months, Netanyahu has held talks with some of the presidential candidates in the U.S., including Republican Rudi Giuliani and John McCain, in order to rally their support for the divestment efforts.
On Monday, Netanyahu met with Democratic candidate Barack Obama to discuss this issue.