(Adds quote from official, context)
By Nelson Bocanegra and Carlos Vargas
BOGOTA, March 17 (Reuters) - Colombia's economy grew 4.6 percent in 2014, a hair below the government forecast, with construction providing much of the momentum in the face of falling oil prices, though fourth-quarter weakness surprised analysts.
The government of the Andean nation had forecast 4.7 percent growth in gross domestic product for 2014 after the economy had enjoyed sustained growth above 4 percent each year since 2010. Still, the price tumble in oil, Colombia's most valuable export, has led to expectations of more subdued expansion from now on.
Indeed, GDP growth in the fourth quarter slowed to 3.5 percent as the oil-price drop accelerated. Analysts had forecast growth of 4 percent in the quarter, well below the 6.1 percent GDP expansion in the same period of 2013.
The government forecasts growth of 4.2 percent this year.
In full year 2014, construction rose 9.9 percent, social services grew 5.5 percent and financial services increased 4.9 percent. Mining activity dropped 0.2 percent during the year.
The fourth-quarter slowdown may push Colombia's central bank to keep its benchmark interest rate at 4.5 percent when it makes a policy announcement on Friday as it seeks to contain inflation which has crept up recently, without snuffing out growth. Several board members at the bank have said controlling inflation is the top priority.
"This data confirms our main scenario, which is that the best decision at the moment is leaving the interest rate on hold because although inflation has increased, risks associated with economic growth are important," said Camilo Perez, Banco de Bogota's head of research.
Finance Minister Mauricio Cardenas said slower growth linked to oil prices provides an opportunity for weaker sectors to contribute more to economic activity.
"The government must support this transition and not just leave it to market forces," Cardenas told reporters.
The rapid weakening of the peso recently has made Colombian exports more competitive.
A large share of Colombia's commodity-led economy, which also exports coal and coffee, remains informal with rural poverty still widespread despite fast urban expansion.
Billions of dollars of investment in Colombia's oil sector have enabled it to ramp up output in the last few years, but the halving of crude prices since June will hit harder in 2015 with prices seen lower for the full year.
The government earns substantial royalties and taxes from the dominant oil company, Ecopetrol, in which it has an 88 percent stake.
Late last year, the government pushed through a tax reform that helps compensate for the drop in oil income, and last month it announced it would delay 6 trillion pesos ($2.24 billion) in spending.
For graphics of key Colombian economic indicators, see:
link.reuters.com/hec32w (Reporting by Bogota newsroom; Writing by Peter Murphy; Editing by Helen Murphy, W Simon and Peter Galloway)