France's weaker sovereign rating will receive its first big test tomorrow as the country aims to sell up to €8.7 billion (Dh40.5bn) of treasury bills.
France's borrowing costs are likely to increase after it was stripped of its top credit rating by Standard & Poor's.
The debt sale comes as concerns build about the health of the €440bn euro-zone bailout fund after nine nations in the zone were downgraded by the ratings agency.
"It will push up the price France pays to borrow its debt. When there's a downgrade it tends to have an impact across the board and will create complications for French banks, once among the pillars of the euro-zone economy," said Jarmo Kotilaine, the chief economist of NCB in Saudi Arabia.
"It will also make it more difficult to fund additional contributions, if required, to the European Financial Stability Facility [EFSF]."
France and Austria on Friday had their ratings cut to "AA plus" from "AAA" and face the risk of further downgrades, S&P said. Italy, Spain and Portugal had their ratings cut by two notches. The other affected countries were Cyprus by two notches and Malta, Slovakia and Slovenia by one notch each.
Overall, S&P gave 14 countries a "negative outlook", which it said meant a one-in-three chance of each country being downgraded further by next year.
"In our view, the policy initiatives taken by European policymakers in recent weeks may be insufficient to fully address ongoing systemic stresses in the euro zone," S&P said.
Data from JPMorgan Chase shows 10-year yields for the nine sovereign borrowers that lost "AAA" ratings between 1998 and the US's downgrade in August increased an average of two basis points.
It increased two basis points on average in the week after.
But the downgrades also land a blow to the ability of the EFSF to fight the euro-zone crisis. As France is responsible for contributing 20.4 per cent of the fund, it is likely the EFSF may also lose its top rating, say economists.
If that happens, it will threaten hopes of the fund being expanded from €440bn to €1 trillion, a rise many experts believe is needed to stem the turmoil.
The EFSF is funding rescue packages for Greece, Ireland and Portugal partly through bond sales. It is scheduled to sell up to €1.5bn in six-month bills this week.
Before S&P's actions, signs of optimism had been emerging in the euro-zone fund. Borrowing costs fell for Italy and Spain in bond sales on Thursday and the European Central Bank said it had stemmed a credit crunch for the single-currency bloc's banks.
But in a further twist in the crisis, Greece's creditors on Friday suspended talks with its government after failing to agree how much money investors would lose by swapping the nation's bonds. The disagreement raises the risk of the country defaulting on its debt.