Updates after market close

April 2 (Reuters) - Britain's FTSE 100 fell on Wednesday as investors awaited details of U.S. President Donald Trump's tariff plans in the latest escalation of a global trade war that has heightened worries about global growth and inflation.

The blue-chip stocks index .FTSE fell 0.3%, while the midcap FTSE 250 index .FTMC gained 0.3%. Gains in the pound GBP=D3 weighed on the export-focused FTSE 100, as the dollar lost ground ahead of the tariff announcement.

Trump, who has kept the world guessing on the details of the plans for weeks, is set to announce sweeping reciprocal tariffs on global trading partners at 2000 GMT.

The tariffs, which will take effect immediately, are expected to trigger price increases, prompt retaliatory measures from affected countries and disrupt decades of established trade practices.

However, British finance minister Rachel Reeves said London would not rush into action to counter any tariffs, as it doesn't want to risk undermining a possible trade deal with Washington.

Aerospace and Defence .FTNMX502010 stocks led the sectoral declines, down 2.1%

Rolls Royce RR.L and BAE Systems BAES.L were among the top losers in the FTSE 100 index, down 3% and nearly 1%, respectively.

Heavyweight healthcare firms fell alongside European peers ahead of the tariffs announcement. The pharma and biotech .FTNMX201030 index fell 1.4% to its lowest close in nearly a month.

AstraZeneca AZN.L was the biggest drag on the blue-chip index, down 1.2%.

Bakkavor BAKK.L gained 7.9%, among the biggest percentage gainers in the midcap index, after rival Greencore GNC.L agreed to buy the food manufacturer for 1.2 billion pounds.

Ocado's OCDO.L 5.5% jump also helped boost that index.

Chemring CHG.L rose nearly 3% on a 251 million-pound ($325 million) multi-year missile contract from Britain's Ministry of Defence.

Meanwhile, a survey showed that pay awards by British employers cooled in the three months to February, aligning with an official gauge of slowing wage growth that could keep the Bank of England on track to reduce borrowing costs later this year.

($1 = 0.7714 pounds)

(Reporting by Ragini Mathur in Bengaluru. Editing by Vijay Kishore and Mark Potter)

((Ragini.Mathur@thomsonreuters.com;))

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