SCOTTSDALE, Ariz., March 19 (Reuters) - U.S. agricultural exports could be at risk in any retaliation over tariffs implemented by the White House, U.S. Secretary of Agriculture Sonny Perdue said on Monday.

Tension over trade has been simmering in agribusiness circles for months, after the White House slapped duties on imported washing machines and solar panels - and, more recently, President Donald Trump's plan to impose sweeping tariffs on steel and aluminum.

The steel and aluminum tariffs are set to go into effect this week.

Perdue said that while the United States is not currently in a trade war, there have already been repercussions seen in response to the White House's moves.

"There's certainly some trade disruptions based on aluminum and steel tariffs," Perdue said on the sidelines of the National Grain and Feed Association's annual convention.

Perdue did not say what these trade disruptions have been so far, nor if they have directly impacted U.S. commodity agriculture, which has been struggling with low prices and global glut of supplies.

Initial exemptions to the metals tariffs have been granted to Mexico and Canada as negotiations over a revamped North American Free Trade agreement continue. Exemptions for other countries could help ease tensions among other trading partners, Perdue said.

Still, the top U.S. farm official said he believed agricultural and farm products were the "tip of the retaliatory spear" and would be likely targets for angry trading partners.

WORRIES MOUNT
China has opened an antidumping investigation into U.S. sorghum, seen by some as a response to White House actions on washing machines and solar panels. Beijing also began enforcing stricter quality standards as of Jan. 1 on U.S. soybeans, the top agricultural export from the United States in terms of value.

Farm groups fear that China, which imports more than third of all U.S. soybeans, could slow their purchases of agricultural products, heaping more pain on the struggling U.S. farm sector.

Their worries continued to grow on Monday. The Trump administration is said to be preparing tariffs against Chinese information technology, telecommunications and consumer products in an attempt to force changes in Beijing's intellectual property and investment practices.

The European Union, in response to the metals tariffs, has targeted a slate of U.S. products from rice and orange juice, to makeup and motorcycles.

"Retaliation is tit-for-tat and retaliation is possible, but it's not up to us how other countries will react," Perdue said. (Reporting by Karl Plume Editing by P.J. Huffstutter and Tom Brown)