The White House took a step Monday toward placing new tariffs on $300 billion of Chinese goods by submitting the proposal for public comment.

The move comes the same day that Trump confirmed he planned to meet with Chinese President Xi Jinping at the G-20 Summit in Japan in late June to discuss trade.

The administration formally submitted the proposal for 25% tariffs on $300 billion worth of goods for public comment on Monday, a required step before they can officially be adopted. The administration will take comments on the proposal through June 17.

The proposed list of items covered "excludes pharmaceuticals, certain pharmaceutical inputs, select medical goods, rare earth materials, and critical minerals," the U.S. Trade Representative's Office said, without elaborating.

The items that are covered include food, agricultural products, textiles, ceramics, glass, metals, sporting goods, and car parts, among other products.

Trump told reporters earlier Monday that he hadn't committed yet to following through with the tariffs. "I haven't made that decision yet," he said.

[Related: Natural gas industry raises alarm over Trump's trade war with China]

The administration currently has 25% tariffs on $250 billion worth of Chinese goods. Tariffs on an additional $300 billion would cover virtually all imports to the U.S. Trump has said the increases were to pressure China to reaffirm pledges it made in previous trade negotiations.

"We had a deal with China. It was 95% there, and then my representatives, Secretary [Steven] Mnuchin and [U.S. Trade Representative] Bob Lighthizer, went to China and they were told the things that were fully agreed to were not agreed to," he said. "I said, 'Fine. Put on the tariffs.'"

Beijing said Monday that it would hike tariffs on $60 billion in U.S. goods to as high as 25% in retaliation for the U.S. move.