Britain is asking the European Union to pull all of its ambassadors out of Iran.
If approved, the move could send a powerful signal of EU unity.
Britain wants the pull-out in response to Iran detaining some of their embassy staff in Tehran. Sweden, which currently holds the EU presidency, wants to maintain relations with Iran.
The Iranian crackdown is the cover story of next week's World Magazine, which hits news-stands Friday.
For more on the Iranian situation, click play for comments from World Magazine reporter Mindy Belz.