By John Revill and Terje Solsvik

ZURICH (Reuters) - The Swiss and Norwegian central banks became the latest European rate-setters to ease monetary policy on Thursday, citing a weaker inflation outlook that contrasted sharply with the Federal Reserve's warnings about higher U.S. prices.

The Bank of England kept rates on hold as expected, while flagging that they would remain on a "gradual downward path" in a finely balanced statement that also acknowledged "heightened unpredictability" in the global environment.

U.S. President Donald Trump's haphazard threats of heavy trade tariffs and an escalating Israel-Iran conflict have left top central banks trying to steer policy in conditions of near-unprecedented uncertainty for the global economy.

Speaking after a two-day meeting where Fed policymakers kept rates on hold, the U.S. central bank's Chair Jerome Powell on Wednesday laid out how import tariffs imposed on America's trading partners will drive up prices for U.S. consumers.

Trump is due in coming days to say whether tariffs currently pegged at a 10% baseline will rise - in some cases to more than double that level - in a move seen weakening the global economy and so keeping a lid on inflation pressures in many countries.

"Inflationary pressure has decreased compared to the previous quarter," the Swiss National Bank said as it cut rates by 25 basis points to zero and did not rule out returning to negative rates.

In a move that took most analysts by surprise, even Norway's central bank - long the most hawkish of major central banks - also cut its policy rate by 25 basis points and said there were more cuts to come due to a more benign outlook for prices.

"Inflation has declined since the monetary policy meeting in March, and the inflation outlook for the coming year indicates lower inflation than previously expected," Governor Ida Wolden Bache said of inflation which slowed to 2.8% in May.

That mirrored the view taken by Sweden's central bank, which cut its key interest rate to 2.00% from 2.25% on Wednesday and said that, with price pressures weak, it may ease further before the end of the year to boost sluggish growth.

On June 6, the European Central Bank cut its main interest rate for the eighth time in the past year and signalled a pause in policy easing at least next month because inflation was now safely back at its 2% target after three years of overshooting.

CAUTION, LITTLE CONVICTION

Earlier this week the Bank of Japan kept interest rates steady and said it would move cautiously in removing remnants of its massive, decade-long stimulus. Governor Kazuo Ueda said the BOJ's near-term focus was on downside risks, notably the hit from U.S. tariffs.