Of the 44 countries that must approve the treaty, only Japan has done so.

The upper house must still approve the treaty, which is not in doubt.

However, there was still disagreement tonight over how many countries would have to approve the treaty before it went into effect.

A second referendum held on 2 October 2009 approved the treaty.

The Senate must approve the treaty by a two-thirds majority before it can take effect.

The country did narrowly approve the treaty on Sept. 20.

The total was seven more than the two-thirds majority required by the Constitution to approve international treaties.

If French voters approve the treaty, they will probably do so only by a narrow margin.

A two-thirds vote of the Senate is required to approve the treaty, which would mean 67 senators if all 100 were present.

And if not, what steps must the Senate take to protect its constitutional role of approving treaties?