The FTSE 100 was down 0.3 percent by 0711 GMT after  falling as much as 0.7 percent. Midcaps were 0.2 percent lower.

Trump's threat to impose additional tariffs on Chinese goods hit Asia-exposed financial stocks. HSBC and Prudential  were among the biggest drags on the blue-chip index.

Industrial groups Melrose and Ashtead, which are vulnerable to uncertainties in the global market, lost 2.5 percent and 1 percent respectively.

On the midcap index, Security group G4S slumped 8.2 percent and headed for its worst day in six months after Garda World said on Sunday it would not make an offer for the company.

Shares in Domino's Pizza, Britain's biggest pizza delivery firm, led declines on the FTSE 250. Its shares fell 10.5 percent after the company said it no longer expects its international business to break even this year.

AIM-listed Purplebricks dropped 7.5 percent after the online estate agent said its founder and chief executive, Michael Bruce, would quit immediately and the company would wind down its Australian operations and reviews its U.S. business.