TOKYO, June 20 (Reuters) - Japan's Nikkei share average

reversed early gains to trade lower on Friday as geopolitical

risks surrounding the Middle East conflict weighed on sentiment.

As of 0208 GMT, the Nikkei was down 0.1% at

38,442.36, after rising as much as 0.4% earlier in the session.

The index is set to rise 1.6% for the week.

The broader Topix fell 0.29% to 2,784.02 but is on

course to post a 1% weekly gain.

"With the absence of market-moving catalysts, uncertainties

surrounding the Middle East tensions dragged investor

sentiment," said Shoichi Arisawa, general manager of the

investment research department at IwaiCosmo Securities.

The White House said on Thursday that U.S. President Donald

Trump will make a decision within the next two weeks whether to

support Israel in its ongoing conflict with Iran.

"On top of the uncertainties about the conflict in the

region, the outlook of the U.S. tariff plans remains unclear,"

said Arisawa.

Uniqlo-brand owner Fast Retailing ( FRCOF ) fell 2.1%,

dragging the Nikkei the most. Game maker Konami Group ( KNAMF )

lost 1.7%.

Department store operator J.Front Retailing ( JFROF ) fell

2.87% to become the worst performer of the Nikkei.

Chip-testing equipment maker Advantest ( ADTTF ) jumped 4.6%

to become the biggest support to the Nikkei.

Chip-making equipment maker Tokyo Electron ( TOELF ) reversed

early gains to trade 0.25% lower.

Machinery maker Amada ( AMDWF ) rose 5% to become the top

performer of the Nikkei.

Of more than 1,600 stocks trading on the Tokyo Stock

Exchange's prime market, 37% rose and 57% fell, while 4% traded

flat.