FRANKFURT, Dec 10 (Reuters) - The European Central Bank eased policy once again on Thursday to help the euro zone economy cope with the second wave of the coronavirus pandemic, which is almost certain to plunge the bloc into yet another recession this quarter. The ECB increased the overall size of its Pandemic Emergency Purchase Programme by 500 billion euros to 1.85 trillion euros and extended the scheme by 9 months to March 2022, with the aim of keeping government and corporate borrowing costs at record lows. “Uncertainty remains high, including with regard to the dynamics of the pandemic and the timing of vaccine roll-outs,” the ECB said in a statement. “We will also continue to monitor developments in the exchange rate with regard to their possible implications for the medium-term inflation outlook.” It also extended the period during which banks will get a rebate rate on their Targeted Longer-Term Refinancing Operations (TLTRO) by one year to June 2022. The move is unlikely to surprise as the ECB has made it clear for weeks that more easing was coming and that bond purchases along with liquidity facilities for banks would form the backbone of any policy response. The ECB has also argued in the weeks coming up to the decision that its job will be to keep borrowing costs at their current level for longer rather to push them down even more. In line with that guidance, the bank kept interest rates unchanged at record lows, although it maintained a long-standing pledge to cut them further if necessary. The ECB’s deposit rate now stands at minus 0.5% while the main refinancing rate is unchanged at 0%. Attention now turns to ECB President Christine Lagarde’s 1330 GMT news conference, at which she will also unveil fresh macroeconomic projections, including initial forecasts for 2023. (Reporting by Balazs Koranyi; Editing by Catherine Evans)