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FTSE 100 and FTSE 250 flat

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Aerospace and defence stocks add sectoral gains

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WH Smith ( WHTPF ) falls after revising high street business sale terms

June 30(Reuters) - London's stock indexes were mixed on Monday as a relief rally driven

by easing geopolitical tensions and U.S. tariffs fizzled out, while midcaps were set for their

largest quarterly gain in more than four years.

Both the blue-chip FTSE 100 and the FTSE 250 were flat by 1100 GMT. Last week, the indexes

advanced after a truce between Iran and Israel, increased prospects of a dovish Federal Reserve,

and some easing of tariff pressures.

The midcap index is set for its best quarterly showing since October 2020.

Domestically focused stocks have been relatively insulated from tariff disruptions, as the UK

remains the only country with a trade agreement with the United States.

The FTSE 100 has gained 7.7% so far this year, already exceeding its annual gains

recorded since 2021.

Aerospace and defence stocks were up 1.2%, boosted by a 1.7% gain in

Rolls-Royce, after the U.S.- UK trade deal came into effect and removed the 10% tariff on

aircraft engines and parts.

Investors are closely monitoring further U.S. trade agreements ahead of former President

Trump's July deadline.

Data showed Britain's economy grew at its fastest pace in a year during the first quarter of

2025; however, analysts expect growth to slow for the rest of the year.

Among individual stocks, WH Smith ( WHTPF ) fell 2.7% to the bottom of the FTSE 250, after

the company said it would receive less cash than expected from the sale of its UK high street

business to Hobbycraft owner Modella Capital.

Pharmaceutical giant GSK was down marginally after a U.S. senator said Friday she

was launching an investigation into the company's discontinuation of a widely used asthma

inhaler for children.

Gas owner Centrica was among the FTSE 100's worst performers after J.P. Morgan

downgraded its stock.