1.   Among them are unilateral sanctions including limiting flights between the U.S. and Europe and other sanctions, White House officials said.

2.   Among them are unilateral sanctions including limiting flights between the U.S. and Europe and other sanctions, four White House officials said.

3.   And unilateral economic sanctions are by no means new.

4.   Any new unilateral economic sanction must expire after two years unless Congress or the president acts to reauthorize them.

5.   A new study says unilateral economic sanctions rarely work.

6.   A look at the effect of unilateral sanctions.

7.   But increasingly, politicians and foreign-policy analysts are questioning the value of unilateral sanctions because they can conflict with other national interests.

8.   Companies have stepped up their opposition to unilateral sanctions the U.S. enforces against the likes of Cuba, Libya, Sudan and Iran without the support of European allies.

9.   Dunham has long called for an end to unilateral sanctions, which he said only block U.S.-based energy companies from competing internationally.

10.   EU members have distanced themselves from unilateral U.S. sanctions in the past.