The euro hit its highest in nearly a month against the dollar on Monday after eurozone finance ministers agreed to a rescue package for Greece, but gains were pared after cautionary comments from Germany.

The proposed massive financial safety net boosted investor appetite for riskier assets. However, comments from the German finance ministry injected some uncertainty into the equation. A spokesman said a summit of European leaders would be needed to activate aid for Greece and the German Bundestag would also need to be consulted. The European Commission said no leaders' summit would need to be called to activate the aid. "They highlight exactly the uncertainties. We still don't know what the trigger is for an aid being released. It would appear that we haven't reached that yet. It doesn't completely set out the framework the market wants to see," said Adam Cole, global head of FX strategy at RBC Capital Markets. "Uncertainty associated with the euro still exists." The euro rose as high as $1.3691, its highest since mid-March, before trimming gains to the session low of $1.3588 in Europe. It was up 0.7 percent on the day at $1.3595. Traders in Europe reported option-related orders either side of $1.3600 shackling the rate ahead of the New York cut. Stops were, however, said to be building through $1.3570 and $1.3550.