President Barack Obama’s administration on Wednesday notified Congress it will start free-trade talks with Japan, bringing the world’s third-largest economy into U.S.-led negotiations on a regional free-trade pact.

“The participation of Japan, a major U.S. trading partner as well as close ally, further increases the economic significance of a TPP (Trans-Pacific Partnership) Agreement,” acting U.S. Trade Representative Demetrios Marantis said in a letter to congressional leaders.

The 90-day notification was expected after U.S. and Japanese negotiators reached a deal on April 12 on the terms of Japan’s entry into the TPP talks, which are now in their fourth year. . It could clear the way for Japan to participate in the July round of TPP talks.

The United States and the 10 other countries already involved in the TPP talks on Saturday formally approved Japan’s entry into the negotiations at a meeting of regional trade ministers in Indonesia.

Marantis sought to reassure lawmakers that Japan’s participation would not slow down the TPP negotiations, which are slated for conclusion by the end of the year, and that Japan would not refuse to negotiate in sensitive agricultural and manufacturing sectors of interest to U.S. exporters.

“Japan has confirmed it will participate positively and constructively in the negotiations. Japan also confirmed that it will subject all goods to negotiations – both agricultural and manufactured goods – and will join with the other TPP countries to achieve a high-standard and comprehensive agreement this year,” Marantis said.

The White House sees the TPP pact as part of its economic rebalancing toward Asia. It also plans to launch free-trade talks with the 27-nation European Union in coming months.

Countries around the world are moving increasingly toward regional free-trade agreements in the absence of any progress toward a comprehensive world trade deal.

Detroit-based auto makers, particularly Ford Motor Co, have lobbied against Japan joining the TPP talks.

They say the agreement will open the door for more imports from Japan, without tearing down barriers that they say keep U.S. autos out of Japan’s market.

In addition to the United States and Japan, TPP countries include Australia, Brunei, Canada, Chile, Malaysia, Mexico, New Zealand, Peru, Singapore, and Vietnam.

The 17th round of TPP talks is scheduled for May 15-24 in Lima, Peru. It is expected to be followed by an 18th round sometime in July that could be the first time that Japan participates in the negotiations.