The euro zone economy will mark its best year in a decade and maintain solid growth well into 2018, according to economists in a Reuters poll.

The economists said the risk was that their forecasts might not be optimistic enough. 

Euro zone inflation, last clocked at 1.4%, is expected to stay below the European Central Bank's target of just under 2% until at least the second half of 2019, according to the poll of over 80 economists taken this week. 

Euro zone economic growth has been surprisingly robust this year, outpacing both the US and Britain simultaneously for the first time since the 2007-08 financial crisis.

It also marked one of the most synchronous upturns across the euro zone economies. 

Over 90% of 40 economists who answered an extra question said they were confident the current upswing in economies across the 19-nation euro zone would last through the forecast horizon. 

Only four respondents said they were not. 

Such a high degree of confidence in above-average performance for the euro zone has never been captured in Reuters polls stretching back since the financial crisis, and indeed has been a rarity ever since the euro was launched in 1999.

60% of respondents also said the risks to their growth forecasts were skewed more to the upside, with 30%saying they were balanced and only 10% saying it could be worse.  

For inflation, a little over half said the risks to their forecasts were balanced, over 35% of the economists said they were skewed more to the upside and less than 10% said the risks were inflation would be even weaker.

The results suggest forecasters appear unfazed by political risks to the euro zone economy, including the negotiations with Britain on its exit from the European Union, set for 2019. 

The UK economic outlook is looking much less positive. 

A Reuters poll last month said the most likely eventual outcome of those negotiations would be an EU-UK free trade agreement. But the chances of a disorderly Brexit - where no deal is agreed - crept up to 30%. 

The solid outlook for euro zone growth supports the European Central Bank's decision last month to begin reducing its quantitative easing programme by half to €30 billion a month from January, with purchases to continue up to September 2018. 

But the ECB left the door open for an extension to the monthly asset purchases beyond September next year, in its fight to bring inflation back to its target. 

That has kept a lid on expectations for further appreciation in the euro - already up over 11% in 2017 against the dollar - over the coming year, according to a Reuters poll of foreign exchange strategists earlier this month. 

The latest poll showed the ECB is expected to hold its refinancing rate at zero percent and deposit rate at -0.4% up to the end of next year. 

Expansion has picked up speed in the euro zone this year, with the economy growing 0.6% in the third quarter on a quarterly basis. 

It was expected to grow 0.5% in the current quarter to to the end of next year and then at 0.4% a quarter in each quarter after that for the first half of 2019. 

Annual growth was forecast to average 2.2% this year, 1.9% in 2018 and 1.7% in 2019, compared to 2.2%, 1.8% and 1.6% respectively in the previous poll. 

While the ECB has already spent over €2 trillion buying mainly government bonds since March 2015 in an effort to bring inflation back up to target, price pressures still remain weak. 

Euro zone inflation is forecast to average 1.5% this year, 1.4% next year and 1.6% in 2019, similar to predictions made in an October poll.