SINGAPORE, April 25 (Reuters) - U.S. wheat futures stretched gains to a fourth session running on Friday on supply risks due to dry U.S. weather and mounting tensions in Ukraine.
* Chicago Board of Trade wheat for July delivery was up half a percent at $7.00 a bushel by 0049 GMT, adding to Thursday's 2 percent jump.
* Expected rain in the U.S. Plains fuelled a drop in wheat prices on Monday, but traders said showers this week have missed some very dry regions in the southern Plains.
* Ukrainian forces killed up to five pro-Moscow rebels as they closed in on the separatists' military stronghold in the east, and Russia launched army drills near the border in response, raising fears its troops would invade.
* Corn rose 0.4 percent to $5.09-1/2 per bushel and soybeans gained 0.2 percent to $14.72-3/4.
* The dollar came under pressure against the yen as rising tension in Ukraine undermined optimism about U.S. economic growth following strong U.S. durable goods data.
* Asian stocks struggled to rise as the impact of upbeat U.S. economic data and robust U.S. tech shares faced off against fears of an escalating Ukraine crisis.
DATA AHEAD (GMT)
1345 U.S. Markit Services PMI Final April
1355 U.S. Univ of Michigan sentiment index Final April
(Reporting by Manolo Serapio Jr.; Editing by Miral Fahmy)