(Adds quotes, details on decision)
By Julia Symmes Cobb and Nelson Bocanegra
BOGOTA, July 27 (Reuters) - Colombia's central bank lowered the benchmark interest rate to 5.50 percent on Thursday in a bid to stimulate economic growth as analysts and the government reduce their growth predictions for the year.
In its sixth consecutive rate cut, the board reduced the lending rate by 25 basis points, as expected by the majority of analysts in a Reuters survey last week.
The seven-member board has been grappling for more than two years with the twin pressures of falling gross domestic product growth, caused by the global drop in oil prices, and inflation well above the 2 to 4 percent target range.
Weak growth and a reduction in crude price projections were top factors in the decision, policymakers said in a statement.
The meeting came a few days after the government cut its growth forecasts for this year and next to 2 percent, down from a previous forecast of 2.3 percent, and 3 percent, lower than an earlier projection of 3.5 percent.
Some analysts expected the board would also lower its forecast, but bank chief Juan Jose Echavarria said it would hold off any modifications until its quarterly inflation presentation in August and that policymakers expect better growth during the second half of the year.
"It's possible the technical team will take the prediction lower, but there is enormous uncertainty, so we have decided to wait two or three weeks, when we do the inflation report and will have new data," Echavarria said.
"It will not be far from 1.8 percent, but it could be lower," he said, adding that he sees growth for 2018 at 2.5 percent or 3 percent. "We think the Colombian economy has hit bottom and that we will grow more in future."
In the 12 months to June, consumer price growth fell to within the target range for the first time since January 2015, hitting 3.99 percent.
The factors that caused inflation gains, including higher food prices, continue to fade, the board said, but prices may increase again slightly during the remainder of the year and there is uncertainty about when the indicator will reach the ideal target of 3 percent.
The decision was backed by six of seven board members, the statement said. The remaining member voted to hold the rate steady. (Reporting by Julia Symmes Cobb and Nelson Bocanegra; Editing by Dan Grebler)