The cost of selling debt rose for the first time since the National Treasury Management Agency resumed bond auctions last year.

The NTMA said it sold €750m of 15-year debt at a yield of 2.2% compared to 1.6% four months ago.

The country is already fully funded for the rest of the year and has raised €11 billion out of a guided range of €12-15 billion of debt to fund the State for 2016, limiting its exposure to jittery markets. 

However, the NTMA was able to sell 30-year debt at a record low yield of 1.3% just three months ago before yields across the euro zone rose.

A broad market sell-off began in April when fears of a prolonged period of deflation receded.  

Spain also auctioned €5.8 billion of debt at higher yields today as a raft of debt sales in Rome, Dublin and Madrid stretched investor demand. 

The NTMA's auction received 2.9 times more bids than the value on offer compared, with demand slightly higher than the 2.65 bid-to-cover ratio across the three previous bond sales. 

Yields at Irish debt sales are still well below those seen when the NTMA began raising debt periodically in 2012, two years after it was cut off from bond markets. 

The NTMA had to offer an interest rate of 1.8% to sell three-month money in July, 2012. 

The economy has rebound from the crisis that forced it into a three-year aid programme in 2010 to grow faster than any other in the European Union last year and Standard & Poor's raised Ireland's credit rating by one notch to 'A+' last week. 

"We were pleased with the level of demand despite recent market volatility. While the yield is higher than our last 15-year bond auction, our borrowing costs remain low by historical norms," the NTMA's Director of Funding Frank O'Connor said.