WASHINGTON — The Trump administration is suspending a tariff hike on $250 billion in Chinese imports that was set to take effect Tuesday, and China agreed to buy $40 billion to $50 billion in U.S. farm products as the world’s two biggest economies reached a cease-fire in their 15-month trade war.

The White House said the two sides made some progress on the thornier issues, including China’s lax protection of foreign intellectual property. But more work remains to be done on key differences in later negotiations, including U.S. allegations that China forces foreign countries to hand over trade secrets in return for access to the Chinese market.

The U.S. and Chinese negotiators have so far reached their tentative agreement only in principle. No documents have been signed.

President Donald Trump has yet to drop plans to impose tariffs that are set to take effect Dec. 15 on an additional $160 billion in Chinese products — a move that would extend the sanctions to just about everything China ships to the United States. The December tariffs would cover a wide range of consumer goods, including clothes, toys and smartphones and would likely be felt by many American shoppers.

While providing scant details of just what was agreed to Friday, the White House said Beijing has pledged to be more transparent about how it sets the value of its currency, the yuan.

China has also agreed to open its markets to U.S. banks and other financial services providers.