WASHINGTON (Reuters) - Fifty U.S. senators from both parties called on Thursday for President Donald Trump’s administration to begin negotiating a bilateral trade agreement with Taiwan, part of a push by lawmakers for stronger U.S. action to counteract China.

The group of 42 Republicans and eight Democrats sent a letter to Trade Representative Robert Lighthizer citing Taiwan’s record as a U.S. economic partner and security ally, and encouraging him to begin the formal process of negotiating a comprehensive trade agreement.

Taiwan has long sought a free trade agreement with the United States, its most important supporter on the international stage, but Washington has complained about barriers to access for U.S. pork and beef.

In August, Taiwan paved the way for an eventual deal by announcing an easing of restrictions on the import of U.S. beef and pork that is expected to go into effect on Jan. 1.

Taiwan-U.S. trade last year was worth $85.5 billion, with the United States running a $23.1 billion deficit. Taiwan was the United States’ 14th biggest export market in 2019.

The United States, like most countries, has no official relations with Taiwan, which is claimed by Beijing as sovereign Chinese territory. China has been stepping up its military activities near the island.