(Updates with context, comment, chart)
By Dhara Ranasinghe
LONDON, Feb 4 (Reuters) - The pool of negative-yielding government bonds in the euro area expanded in January to its biggest since September, Tradeweb data showed on Tuesday, reflecting a renewed push into fixed income as coronavirus fears gripped markets.
The volume of bonds with a negative yield, where investors are effectively paying governments or corporations to own their debt, had started to shrink late last year as concern over a bitter trade war eased and economic data improved.
But China's coronavirus outbreak and its rapid spread have renewed concern about the global growth outlook -- putting downward pressure on yields of safe-haven sovereign bonds.
On the Tradeweb platform, the volume of euro zone government bonds with negative yields stood at 5.27 trillion euros ($5.83 trillion) at the end of January, roughly 65% of the total 8.09 trillion euro market. That was up from 4.14 trillion euros at the end of December, Tradeweb said.
The January tally was the highest since September, when the pile of negative-yielding debt hit a record 5.63 trillion euros against a backdrop of heightened trade war jitters.
For an interactive version of chart below, click: tmsnrt.rs/35bJCC8
"Obviously, the coronavirus and uncertainty surrounding that is having an impact on risk appetite," said Marchel Alexandrovich, European financial economist at Jeffries in London.
"We're going to be in that state until we get a sense that the spread of the virus has peaked and can then assess what impact that's having on the global economy."
The coronavirus outbreak comes at a bad time for the world economy, hit last year by a U.S./China trade war.
European Central Bank vice president Luis de Guindos said on Monday that the ECB sees early signs of stabilisation in the global economy but cautioned that the coronavirus outbreak is creating uncertainty.
Globally, the pool of debt yielding less than zero percent stands at close to $14 trillion, up from around $11 trillion in mid-January but off peaks around $17 trillion hit in September, analysts said.
Ten-year yields on German government bonds, regarded as one of the safest assets in the world, fell almost 26 basis points in January to around -0.40% -- notching up their biggest monthly falls since August.
French 10-year bond yields pushed decisively back below 0% last month and 30-year German yields are about 10 bps away from turning negative again.
Poland meanwhile became the first emerging market country to sell a mainstream government bond with a sub-zero interest rate on Monday, marking another major milestone in the post-crisis plunge in global borrowing costs.
Reporting by Dhara Ranasinghe; Editing by Catherine Evans