* Traders await details on Chinese buying
* Favourable Brazil crop weather limits CBOT soy
* Firming global prices underpin CBOT wheat
CHICAGO, Dec 26 (Reuters) - The most actively traded U.S. soybean futures contract touched its highest price since June 2018 on Thursday on short covering and expectations for increased Chinese demand.
Traders and farmers hope top-importer China ramps up U.S. soybean purchases following an announcement of a Phase 1 trade deal, which includes a commitment by Beijing to increase purchases of American agricultural products.
Details about the timing and size of Chinese purchases remain unknown, and some analysts doubt China's buying will reach Washington's projections for $40 billion to $50 billion.
China is in close touch with the United States on signing the Phase 1 deal, the country's commerce ministry said, adding that both sides are still going through necessary procedures before the signing.
"Who wants to be short right now until we know the details of the Phase 1 trade deal?" said Arlan Suderman, chief commodities economist for broker INTL FCStone.
Chicago Board of Trade (CBOT) March soybeans were up 1-1/2 cents at $9.46-1/4 a bushel by 12:10 p.m. CST (1810 GMT). The contract, which has replaced January as the most actively traded month, set a session high of $9.49. That was the highest price for a most-active contract since June 13, 2018.
Strength in Malaysian palm oil helped support CBOT soy futures, traders said. But soy's advances were constrained by generally favourable crop weather in South America, which competes with the United States for export business.
Brazilian soybean exports typically accelerate early in the new year as farmers harvest their crops, while U.S. exports ease. China bought soy from Brazil, instead of the United States, during the trade war.
"Cheaper South American beans, nearly ideal weather in South America, along with an expected drop-off in export demand are going to limit rallies in beans," said Tomm Pfitzenmaier, analyst for Summit Commodity Brokerage in Iowa.
The most active CBOT wheat contract rose 8-3/4 cents to $5.49-3/4 a bushel, while most active corn futures were up 1/2 cent at $3.88 a bushel.
Wheat futures moved modestly higher on technical buying and support from firming global cash prices, analysts said.
Morocco's government approved a decree on the suspension of customs duty on soft wheat from Jan. 2 to April 30 to ensure a regular supply and price stability on the domestic market.
(Reporting by Tom Polansek in Chicago; Editing by Richard Chang)