WASHINGTON - The US administration has pressed its trading partners via letters to submit their best offers by Wednesday, the White House confirmed Tuesday.

White House Press Secretary Karoline Leavitt said the letters sent from the United States Trade Representative were "just to give them a friendly reminder that the deadline is coming up."

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Leavitt added that the Trump administration officials are still in talks with trade partners to strike deals during the 90-day pause.

Local media revealed that the letters asked trade partners to list their best proposals by Wednesday in several key areas, including tariff and quota offers for the purchase of US industrial and agricultural products as well as plans to remedy any non-tariff barriers.

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The 90-day negotiation window from April 9 to July 8 was established after market volatility forced the White House to pause its "Liberation Day" tariffs imposed on April 2.

The White House did not disclose which economies received the letters.