Barclays, Nomura and Societe Generale will manage the deal, the EFSF said on Monday. Although official guidance has not been released yet, market observers expect the deal to come at around 30-32bp over swaps.

Spreads to swaps are constant in the belly of EFSF's curve from six- to nine-years. EFSF's outstanding 2.625% May 2019s and its 3.375% July 2021s were both bid at mid-swaps plus 25bp straight after the mandate announcement on Monday, according to Tradeweb. Fair value on the new 2020 line, therefore, should also come around 25bp.

The transaction will mark the euro rescue fund's return to markets after it was downgraded by Moody's to Aa1 in November 2012.

EFSF's last issue was a EUR7bn 0.125 percent one-year syndicated deal, the largest ever bond from a supranational issuer, launched just days before the downgrade.

That unusual transaction was a substitute for a three-year issue that was pulled the week before, after Moody's downgraded the long-term debt rating of France, the EFSF's second largest guarantor. Market participants correctly anticipated the same ratings action on EFSF's long-term debt, so turned to a shorter-dated funding solution in the interim.

EFSF plans to raise EUR55-EUR60bn in long-term funding in 2013 to meet disbursements for its programme countries Ireland, Portugal and Greece.