In response to a suggestion made by Russian President Vladimir Putin, the Organization for Security and Cooperation in Europe (OSCE) has agreed to initiate discussions on U.S. plans to deploy a missile-defense system in Central Europe.

The State Department Wednesday called on Iran to allow two detained American women, both with dual U.S. and Iranian citizenship, to return to the United States. The women, an academic and a journalist, went to Iran on visits several months ago and have not been allowed to leave.

A semi-official Iranian news agency reports that Iran is not ready to negotiate with the United States at a major international conference on Iraq, to be held this week in Egypt. The Iranian Students News Agency, ISNA quotes Iranian officials as saying conditions are not right for talks between the two nations.

U.S. Secretary of State Condoleeza Rice is suggesting she will defy a congressional subpoena to testify about the Bush administration's reasons for invading Iraq.

The top U.S. general in Iraq, David Petraeus, says the situation in that country is "very tough." Petraeus told reporters at the Pentagon today that the U.S. war effort faces the most complex challenge he has ever seen as a soldier.

The U.S. House of Representatives has defied President George W. Bush's veto threat and approved a war-funding bill that sets a timeline for the start of a withdrawal from Iraq. The bill passed on April 25 by the House provides an additional $124 billion in war spending for Iraq and Afghanistan, through September 30, as President George W. Bush had requested.

U.S. Defense Secretary Robert Gates was in Poland on April 24 to promote U.S. plans to build a missile-defense shield in Eastern Europe. The Bush administration wants to place 10 interceptor missiles in Poland and a targeting radar in the Czech Republic as part of a defense system that has already been deployed in the United States, Britain, and Greenland.

Russia warned that it could target some of the U.S. missile defense systems that Washington wants to deploy in Poland and Czech Republic, the Interfax news agency reported.

Democratic presidential rivals Hillary Rodham Clinton and Barack Obama urged thousands to make environmental protection a top campaign issue. "Today is Earth Day, and I personally believe every day should be Earth Day," said Clinton. "We have a duty to protect God's creation and we have a responsibility to repair the damage that we do as we go on in life."

The 2008 presidential contenders will debate in cyberspace in early next fall. The political blog Huffington Post, online portal Yahoo and Slate Magazine will host the debates - one for Democratic candidates, one for Republicans - sometime in autumn, with PBS host Charlie Rose serving as moderator, the sponsors planned to announce Monday.

The United States protested a raid by security forces in Kyrgyzstan on a facility where opposition newspapers are printed. The police action in the capital Bishkek early Friday followed several days of protests against the government of President Kurmanbek Bakiyev.

The U.S. plan to install elements of a missile-defense system in Poland and the Czech Republic is expected to be discussed by representatives of Russia and NATO member countries during talks today at NATO headquarters in Brussels, Belgium.