German Chancellor Angela Merkel and French President Francois Hollande released a joint statement Friday saying they will do anything they can to stop the 17 countries that use the euro from breaking up. They didn't offer details.
The euro has been weakening in recent weeks on fears that Spain may need a bailout. But country's economy, the euro zone's fourth-largest, may be too big for Europe to save.
The statement from Merkel and Hollande helped reassure investors that European leaders are committed to help Spain if needed.
Merkel and Hollande's statement came a day after European Central Bank head Mario Draghi made similar comments. His remarks also sent the euro higher Thursday.
The euro rose to $1.2312 late Friday from $1.2286 late Thursday. The euro rose as high as $1.2389 earlier, its highest point against the dollar since July 6.
The British pound rose to $1.5728 from $1.5690. The dollar fell to 0.9757 Swiss franc from 0.9775 Swiss franc and to 1.0041 Canadian dollar from 1.0097 Canadian dollar.
The dollar rose to 78.60 Japanese yen from 78.21 yen.