Portuguese Prime Minister Antonio Costa on Tuesday said it would be "unjustified and counterproductive" to punish his country for overstepping the eurozone's deficit limits.

"This entire process is a contradiction," Costa told reporters, saying that Portugal this year would bring its deficit to under three-percent of GDP, thus meeting EU rules, "without having to turn to plan B or exceptional measures" to cut spending.

Eurozone finance ministers agreed to officially begin a sanctions procedure against Spain and Portugal, a procedure that could entail fines of up to 0.2 percent of gross domestic product (GDP)