WASHINGTON (Reuters) -The announcement by President Donald Trump's administration of the results of a probe into pharmaceutical imports and new sector-specific U.S. tariffs likely remains weeks away, four official and industry sources said, later than initially promised as he focuses on other matters.

Commerce Secretary Howard Lutnick had said in April when the review of whether reliance on foreign drug production threatens U.S. national security was launched that he anticipated that it would conclude between mid-May and mid-June. Global pharmaceutical companies are bracing for the outcome of the investigation, which will usher in sector-specific tariffs that Trump has said could start small and eventually rise to 250%. 

The Republican president said as recently as last week that his plan relies on phased-in tariffs, giving drugmakers time to increase manufacturing in the United States as he pushes to alter what he says are global trade distortions in many industries.

One government official in Europe and a source with knowledge of the White House process, as well as two sources at European drug firms familiar with the process, told Reuters that the report and tariffs announcement was not imminent and likely weeks away. These sources spoke on condition of anonymity.

A White House spokesperson, asked about media reporting indicating that the results of the probe could be several weeks away, cautioned that such reports were pure speculation unless confirmed by the White House. The spokesperson declined to give further details about the timing of the pharma probe or one involving semiconductors.

The investigation is examining pharmaceutical imports ranging from finished prescription drugs to active pharmaceutical ingredients, called APIs, and other raw materials, with the results to be disclosed in a Commerce Department report. 

Lutnick said last month the tariff plan that will be based on the report would be completed by the end of July. Lutnick then said on July 29 it would be two more weeks.

The investigation was launched under Section 232 of the Trade Expansion Act of 1962. While the investigation is ongoing, the pharmaceutical sector has been exempted from the sweeping tariffs imposed by the Trump administration. 

The United States has reached bilateral trade deals with the UK, Japan, South Korea and the European Union that promised more favorable terms for their pharma exports than those expected to be levied on the sector globally.

A European government official said that an announcement before the end of August appears unlikely but cautioned that the timeline could shift depending on other developments. 

A source at a European drugmaker said the Trump administration is focused on the U.S.-Russia summit in Alaska on Friday and therefore no announcement is expected this week.

The source familiar with the White House process said that announcement is unlikely to come this week given other priorities.

That source and one other source said that they expect the Trump administration to announce the results of its national security investigation into semiconductors first, followed by the pharma announcement, putting it a few weeks away.  

The Section 232 provision authorizes the president to adjust imports - including imposing tariffs - if a category of goods is being imported into the United States in quantities that "threaten or impair the national security."

Medical goods historically have been spared from trade wars due to the potential harm to patient access, and drugmakers have said tariffs could undercut other health policy goals outlined by the Trump administration, including lowering drug prices. 

U.S. tariffs on imported pharmaceutical products would mark the latest in a series of sectoral tariffs announced by the administration, following metals and cars, that some economists have predicted will drive up costs for American consumers.