WASHINGTON -- Beijing has proposed big increases in American imports while U.S. President Donald Trump is set to meet a high-ranking Chinese official in the Oval Office, as trade talks between the world's two largest economies reach a critical stage.

The Chinese side has expressed a willingness to drastically raise imports of U.S. liquefied natural gas and semiconductors during talks in Washington.

Two days of ministerial talks between Chinese Vice Premier Liu He and U.S. Trade Representative Robert Lighthizer began Thursday, building on discussions at the deputy level that started earlier in the week.

Trump is to meet with Liu on Friday, the White House said late on Thursday, according to Reuters.

China has presented numerical targets for large purchases of U.S. products, including LNG, soybeans and semiconductors, signaling some progress toward reducing the U.S. trade deficit with China, a source familiar with the negotiations said.

Following the last round of ministerial talks, the White House said on Feb. 15 that the countries will draft memorandums of understanding to put their commitments into writing. Washington and Beijing are aiming to finalize the language as well as a date for their leaders' summit through this week's meetings.

Trump and Chinese counterpart Xi Jinping agreed to intensive trade talks at their summit in December, and the Trump administration plans to raise tariffs on $200 billion worth of Chinese goods if they fail to reach a deal by March 1. With the deadline just around the corner, ministerial talks are now entering their most-critical phase.

If the countries are close to reaching a deal, "there is a possibility that I will extend the date," Trump said Feb. 15.

The White House statement that day stressed that "much work remains." The current round of talks is expected to include discussion of China's intellectual property practices and forced technology transfers. Washington has also criticized Beijing's industrial subsidies as a violation of World Trade Organization rules and pressed Xi to overhaul his "Made in China 2025" initiative to modernize domestic industry.

Negotiators are also discussing foreign exchange issues around the Chinese yuan, said a U.S. Treasury official. Trump has been critical of Beijing's handling of the currency, vowing to label China a currency manipulator during his 2016 presidential campaign.

The U.S. is also calling for mechanisms to ensure China follows through on its agreements. Discussion continues over penalties, including higher tariffs, as part of that framework.

The trade war first flared up when Washington imposed punitive tariffs on China last July. Beijing retaliated with tariffs of its own in a tit-for-tat game. Exports to China from Japan, Southeast Asia and Europe have slowed as a result.

Both presidents are struggling to cope with the trade war's fallout. The U.S. stock market rally on which Trump prided himself has ended, while Xi faces unstable employment at home. Financial and capital markets have already begun to factor in a cease-fire on trade, but a breakdown in negotiations could shock an already shaky global economy.