The head of the International Monetary Fund welcomed a last-ditch vote Wednesday in the US Congress to end a government shutdown and raise the government's debt ceiling.

IMF Managing Director Christine Lagarde described the decision as "important and necessary" but did not directly allude to fears that a failure to pass the measure would have led the United States into default.

"Looking forward, it will be essential to reduce uncertainty surrounding the conduct of fiscal policy by raising the debt limit in a more durable manner," she said.

"We also continue to encourage the US to approve a budget for 2014 and replace the sequester with gradually phased-in measures that would not harm the recovery, and to adopt a balanced and comprehensive medium-term fiscal plan."

The measure adopted by Congress only funds the US government until January 15 and allows it to borrow freely until February 7, leaving open the possibility of another political crisis within months.