Coronavirus lockdowns have hit Chinese growth more than expected, ratings agency S&P said as it slashed its forecast for the second time in two months, while emerging market economies will slow in the second half of this year amid high inflation.

S&P cut its GDP growth prediction for China to 3.3%, in a report, having already downgraded it to 4.2% in May from a 4.9% forecast made in March.

It said higher than expected first quarter growth in many countries meant its 2022 growth forecast for emerging market economies excluding China was unchanged at 4.1%, but sounded a pessimistic note about the rest of the year and 2023.

"The optimism of early 2022 has given way to worries of a sharply weakened global economy," it said in an emailed statement on Wednesday, blaming the Russia-Ukraine war, higher commodity prices, Chinese lockdowns and rising interest rates.

S&P also increased inflation forecasts for a sample of 15 emerging markets, to 7.1% in 2022 and 4.1% in 2023, from 5.9% and 3.5% in March and said it expected inflation to breach most central banks' targets until at least 2024 even as they tighten monetary policy faster.

Meanwhile, Fitch said the Czech Republic, Hungary and Slovakia were the most vulnerable central and eastern European countries to being cut off from Russian gas, due to a high exposure and lack of workable short-term alternatives.

"A complete and sudden cessation of the supply of gas to the EU from Russia is not Fitch's base case. However, it is a risk," the ratings agency said in a note on Wednesday.

The region "would face a large macro shock, including lower and in many cases negative growth, potential sectoral scarring, higher inflation and sustained pressure on public deficits and debt levels," it said.