GRAINS-Wheat extends rally for 4th day on Ukraine, dry U.S. Plains

* Market wary of Ukraine violence, still-dry U.S. Plains

* Corn firm on slow planting, soy recovers from losses

(Updates comments, prices; changes byline/dateline)

PARIS/SINGAPORE, April 25 (Reuters) - Chicago wheat futures extended gains to a fourth session on Friday, trading at a one-week high, as the market remained wary of rising tension in Ukraine and dryness in the U.S. wheat belt.

The latest gains brought Chicago above the $7 threshold and meant it had wiped out losses from the start of the week when expectations of rain relief in the U.S. Plains sparked selling.

Chicago Board of Trade wheat for July had risen 1.2 percent to $7.04-3/4 a bushel by 1239 GMT, its highest since April 17. Front-month May was up 1.1 percent at $6.96-3/4.

"The dry weather condition in the U.S. Plains has been a very persistent supportive factor, but the large price movements recently were because of the renewed tensions in Ukraine," said Vanessa Tan, investment analyst at Phillip Futures.

Ukrainian forces killed up to five pro-Moscow rebels on Thursday in the east of the country, and Russia launched army drills near the border in response, raising fears its troops would invade.

Diplomatic tensions remain high as Russia warned Kiev it would face justice for a "bloody crime" in eastern Ukraine, while Washington said Moscow was running out of time to defuse the crisis before facing further sanctions

"The escalation of the conflict in east Ukraine is ... driving up wheat prices, for Ukraine and Russia combined account for approximately 20 percent of worldwide wheat exports," Commerzbank analysts said in a note.

In the United States, traders say showers this week have missed some very dry regions in the southern Plains, even as rain elsewhere has brought relief to wheat and also delayed planting of corn.

CBOT July corn rose 0.9 percent to $5.11-3/4 per bushel, extending gains this week on concern that rainy weather might continue to stall already-slow spring planting.

July soybeans added 0.8 percent to $14.81-1/4 per bushel as the market continued to attract bargain-hunters after sharp losses this week.

Worries over faltering demand from top buyer China and expectations of increasing imports into the United States, have given a bearish fundamental tone to the oilseed market.

* Prices as of 1239 GMT

Product Last Change Pct Move CBOT wheat 696.75 7.75 +1.12 CBOT corn 505.75 4.50 +0.90 CBOT soy 1483.00 11.00 +0.75 Paris wheat 217.00 1.00 +0.46 Paris maize 186.50 -1.50 -0.80 Paris rape 398.00 -8.75 -2.15 WTI crude oil 101.65 -0.29 -0.28 * CBOT futures prices are in cents per bushel, Paris futures in

euros per tonne, WTI crude oil in dollars per barrel.

(Editing by Muralikumar Anantharaman, editing by David Evans)