LONDON, Oct 13 (Reuters) - Copper prices fell on Tuesday as strong trade data from China, the largest consumer, was offset by a stronger dollar and news that Johnson & Johnson had paused clinical trials of a coronavirus vaccine.

Benchmark three-month copper on the London Metal Exchange (LME) was down 0.7% at $6,689 a tonne at 1605 GMT, but remained close to September's 27-month high of $6,877.50.

Used in power and construction, copper has gained more than 50% since March as China reopened its industry.

U.S. stimulus, a weaker dollar or faster growth outside China could lift prices further, but a resurgence in coronavirus cases could lower them, said Saxo Bank analyst Ole Hansen.

"Probably we have reached as far as we can," he said.

CHINA TRADE: Chinese exports rose 9.9% in September from a year earlier, in line with analysts' expectations and up from a 9.5% increase in August. Imports jumped 13.2% compared to a 2.1% drop in August.

IMPORTS: China's copper imports rose in September to their second highest level on record. Imports in the first nine months of 2020 were up 41% from a year earlier at 4.99 million tonnes.

"China's plan to build strategic reserves is likely to keep imports resilient," analysts at ANZ wrote in a note.

VACCINE: Johnson & Johnson paused clinical trials of a coronavirus vaccine candidate due to an unexplained illness in a study participant.

DOLLAR/YUAN: The dollar rose, making metals pricier for non-U.S. buyers. China's yuan has weakened from an 18-month high hit on Friday, but international banks say it is likely to strengthen again.

JAPAN: Japan's manufacturers are recovering at a glacial pace.

DRC: Democratic Republic of Congo has issued a six-month waiver to an export ban on copper concentrate, the mining minister said.

CHINA PRODUCTION: China's output of zinc rose in September, while nickel, lead and tin production fell, research house Antaike said.

DUTIES: The European Union will impose duties of up to 48% on imports of aluminum extrusions from China.

OTHER METALS: LME aluminum was down 0.1% at $1,853.50 a tonne, zinc fell 0.9% to $2,417, nickel slipped 0.9% to $15,030, lead lost 2.4% to $1,800.50 and tin was 0.1% lower at $18,230.

(Reporting by Peter Hobson; Additional reporting by Mai Nguyen; Editing by Ed Osmond, Susan Fenton and Jan Harvey)