UPDATE 2-Colombia drops full-year growth estimate to 1.8 percent

(Adds revision of growth projection, finance minister quotes)

BOGOTA, Nov 15 (Reuters) - Colombia's government lowered its full-year growth estimate to 1.8 percent on Wednesday as Finance Minister Mauricio Cardenas lamented that the Andean nation's economy was still performing "below potential."

Cardenas announced the lower growth estimate after the government's statistics agency DANE reported that the economy expanded 2 percent in the third quarter compared with the same period a year ago.

That was lower than expected by Cardenas. Colombia has spent two years grappling with the fallout from a recent decline in oil prices and an ongoing drop in domestic consumption.

Agriculture and finance were the top sectors behind third quarter growth, expanding by 7.1 percent and 3.2 percent respectively. The mining and energy sector and construction, important engines of growth, both contracted by 2.1 percent, and manufacturing shrank by 0.6 percent.

Latin America's fourth-largest economy accelerated 0.8 percent during the third quarter versus the second, and grew 1.5 percent between January and September, compared with the same period the year before, DANE said.

"Our economy continues to show signs of sustainable recovery," President Juan Manuel Santos said on his Twitter account. "We knew how to weather the external shock," he added, referring to the drop in oil prices.

Though Cardenas said he was convinced the economy was over the worst, he revised down the government's estimate for 2017 growth from 2 percent previously.

He had expected a third quarter expansion of 2.4 percent.

Growth in the fourth quarter should come in at 2.5 percent, he said.

"The economy still is below potential growth," Cardenas told journalists. "It's something that should be looked at at the next 1/8central bank 3/8 board meeting."

In a bid to stimulate growth, the board has cut 275 basis points from the benchmark interest rate since December, even as it struggled to contain inflation. The seven-member bank board surprised the market in October by trimming 25 basis points from the rate.

The bank's technical team estimates gross domestic product will grow 1.6 percent this year. The board revised upward its 2018 economic growth estimate to 2.7 percent from an earlier prediction of 2.4 percent at its last meeting.

Those estimates justify a more expansionist monetary policy, though future cuts to the interest rate will depend on inflation consolidating at 3 percent, board member Juan Pablo Zarate told Reuters last week.

The October rate cut puts borrowing costs in "lightly expansionist" territory, Zarate added. (Reporting by Nelson Bocanegra and Carlos Vargas; Writing by Julia Symmes Cobb; Editing by Chizu Nomiyama and Tom Brown)