Britain's top share index has given up its gain for this year, after a choppy week in equity markets.
The blue-chip FTSE 100 index finished the week 0.27 per cent lower at 6,550.77. It closed at 6,556.10 at the end of 2014, although it had risen to a record 7,122.74 points in late April.
Oil companies led the decline, as they came under pressure amid sliding oil prices, which had dropped to their lowest in almost 6-1/2 years.
"Ultimately, the commodities market does remain under pressure," Brenda Kelly, analyst at London Capital, said.
Turbulence started earlier this week when the Chinese central bank unsettled global markets. It took steps to devalue the renminbi against the US dollar in a bid to boost its economy.
The People's Bank of China (PBoC) cut the reference point by 1.9 per cent on Tuesday, 1.6 per cent Wednesday and then 1.1 per cent Thursday. But this morning it moved to end the devaluation pattern seen so far this week.
The reference point is a guiding rate, from which trade can rise or fall by two per cent throughout the day.
Brent crude, the global benchmark, has also fallen amid concerns about the Chinese economy and a global supply glut.