UPDATE 1-Argentine January primary budget surplus doubles

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BUENOS AIRES, Feb 19 (Reuters) - Argentina's January primary budget surplus more than doubled from a year earlier, rising more than expected as public spending slowed, the government said on Tuesday.

The surplus rose to 3.39 billion pesos ($1.1 billion), from 1.63 billion pesos a year-ago.

The figure, which excludes interest payments on Argentina's debt, is seen as a gauge of the country's credit-worthiness.

"This is more than double the result in January 2007 and it is a historic record for all months of January," Economy Minister Martin Lousteau told reporters.

"While income grew 46 percent, spending grew 10 percentage points below that, meaning it grew 36 percent, reversing the trend that it had been showing," Lousteau said.

Analysts consulted monthly by the central bank forecast a January primary budget surplus of 2.594 billion pesos according to the average estimate. ($1 = 3.175 Argentine pesos) (Reporting by Cesar Illiano; Writing by Fiona Ortiz, Editing by Leslie Adler)