* South African rand firms as dollar slides for sixth day
* Russian rouble, stocks jump as manufacturing activity rebounds
* Old Mutual slips after suspending interim dividend
* Yuan at over one-year high after strong manufacturing data
By Sagarika Jaisinghani
Sept 1 (Reuters) - Emerging market currencies scaled six-month highs on Tuesday as the U.S. Federal Reserve's accommodative stance on inflation hit the dollar, while stocks gained after upbeat manufacturing data from China signalled a strong rebound in global demand.
An index of emerging market currencies rose 0.4% as the dollar slid for a sixth straight day following Fed Chair Jerome Powell's statement last week that the central bank would allow inflation to run higher than 2% "for some time".
The index has rebounded since a coronavirus-driven crash earlier this year and is now about 2.4% below its January highs, as historic global stimulus drives appetite for risky assets, but analysts cautioned rising COVID-19 cases and geopolitical risks could halt the recent rally.
"Coming out of a stellar summer, markets should not be allowed to breed complacency," said Mizuho Bank's Hayaki Narita.
"The climate may not be as conducive for extending 'risk on' asset market rallies and one-way USD decline, especially amid an unpredictable political weather."
South Africa's rand jumped 1.2% after sliding 2% on Monday amid fears of potential cabinet changes due to infighting within the ruling African National Congress.
But the Turkish lira slipped another 0.3% as geopolitical tensions ratcheted up after it said it would carry out seismic surveys in a disputed area of the eastern Mediterranean until Sept. 12, provoking an angry response from neighbouring Greece.
The Russian rouble bounced off four-month lows and the stock index gained 0.5% as data showed the country's manufacturing activity returned to growth in August after falling for 15 months in a row.
"It will be the right time to get some guidance from central bank officials about the path of the policy rate in light of the recent sharp weakening of the rouble," said Alexey Pogorelov, director at Credit Suisse.
Among stocks, South Africa's Old Mutual slipped 0.4% after putting its interim dividend on hold, withdrawing financial targets and warning of a drop in full-year profit. The wider stock index jumped 1.7%.
A basket of emerging market stocks rose 0.9%, tracking gains in Asia, as data showed manufacturing activity in China expanded at the fastest clip in nearly a decade in August, reducing pressure on policymakers to take bolder steps to avert a deeper global recession.