WASHINGTON—The U.S. on July 17 launched the first salvo in the renegotiation of the 23-year-old North American Free Trade Agreement (NAFTA), saying its top priority for the talks was shrinking the U.S. trade deficit with Canada and Mexico.

In a much-anticipated document sent to lawmakers, U.S. Trade Representative Robert Lighthizer said he would seek to reduce the trade imbalance by improving access for U.S. goods exported to Canada and Mexico under the three-nation pact.

The American Petroleum Institute (API) was cheered by the Trump administration’s recommendations.

“NAFTA provides a strong foundation for the energy flows that occur between the U.S., Canada and Mexico,” said API President and CEO Jack Gerard in a statement. “We applaud this administration’s willingness to consider ways to improve North American energy markets that are already providing enormous benefits to the U.S. economy and consumers. The U.S. is now the largest producer of oil and natural gas in the world, and this coupled with enhanced energy integration with Canada and Mexico will increase long-term U.S. energy and national security.”

Gerard emphasized how the trade pact has supported U.S. jobs and manufacturing in energy and lowered fuel costs for Americans.

“Preserving these benefits is critical, and that includes supporting key provisions like a strong investor state dispute settlement mechanism to protect U.S. companies and ensure they receive fair and equitable treatment,” he said. “As the process gets underway, we look forward to working with the administration and Congress to continue the U.S. energy renaissance.”

For the first time in a U.S. trade deal, the administration also said it wants an “appropriate” provision to deter currency manipulation by trading partners. The move appeared aimed at future trade deals rather than specifically at Canada and Mexico, which are not considered currency manipulators.

The 17-page document asserted that no country should manipulate its currency exchange rate to gain an unfair competitive advantage, an often-cited complaint about China in past years.

Shortly before the release of the document, President Donald Trump lashed out against trade deals and unfair trade practices, saying he would take more legal and regulatory steps during the next six months to protect American manufacturers.

Canadian Minister of Foreign Affairs Chrystia Freeland said the U.S. list was “part of its internal process” although a source familiar with the Canadian government’s thinking said the document was “not earth-shattering.”

Canadian Minister of Foreign Affairs Chrystia Freeland The source said officials from the United States, Mexico and Canada would meet in Washington on July 18 to discuss logistics of the talks. No date has been announced for the NAFTA talks, but they are expected in mid-August.

Mexico’s economy ministry said in a statement it would work “to achieve a constructive negotiation process that will allow trade and investment flows to increase and consolidates cooperation and economic integration to strengthen North American competitiveness.”

Speaking on condition of anonymity, a senior Mexican government official said the list of priorities was “not as bad as I was expecting” and welcomed that the U.S. was not pushing to impose punitive tariffs, as Trump has threatened.

Trade experts have argued that shrinking the yawning U.S. trade deficit will not be achieved through trade deals but rather by boosting U.S. savings.

“The first bullet point shows their preoccupation with bilateral trade deficits and that’s unfortunate,” said Chad Bown, a senior fellow and trade expert at the Peterson Institute for International Economics. “There’s not much that trade policy and trade agreements can do to change those. That’s more of a macroeconomic issue.”

Among the priorities, Lighthizer said the administration would seek to eliminate a trade dispute mechanism that has largely prohibited the U.S. from pursuing anti-dumping and anti-subsidy cases against Canadian and Mexican firms.

There was no mention of active disputes between the United States and Canada over softwood lumber and dairy products, but the document targeted a range of agricultural non-tariff barriers, including subsidies and unfair pricing structures, that are currently at the heart of those standoffs.

USTR said it would seek to strengthen NAFTA’s rules of origin to ensure that the pact’s benefits do not go to outside countries and to “incentivize” the sourcing of U.S. goods. It offered no details on such incentives and did not specify how much of a product’s components must originate from NAFTA countries.

NAFTA has quadrupled trade among the three countries, surpassing $1 trillion in 2015, but the U.S. trade deficit with Mexico exceeded $63 billion last year.