An opinion poll published by Spain's Center for Sociological Investigation (CIS) on Tuesday showed approval ratings of the ruling Popular Party government dropped four percentage points since it won the general elections in November last year.

If an election were to be held today in Spain, Prime Minister Mariano Rajoy's party would win 40.6 percent of the vote as opposed to the 44.62 percent they polled at the elections, the study said.

The last CIS study published in January gave the party 42.7 percent of the vote. Amid a rising budget deficit and crippling unemployment, Spain announced spending of cuts of 27 billion euros (36 billion U.S. dollars) this year to try and balance its books.

The Socialist (PSOE) Party, led by Alfredo Perez Rubalcaba, would poll 29.6 percent in an election today, marginally more that what they polled in November which was the party's worst electoral performance since democracy returned to Spain in 1976.

The left wing Izquierda Unida seems to have gained from PP's loss with ratings up 8.6 percent, while the center-right grouping UpD lost ground and fell to 5.1 percent of the vote from the 5.7 percent it had in the January opinion poll.

In the Basque region, the left-wing Basque nationalist coalition Amaiur overtook the more traditional Basque Nationalist Party in the study. This could be significant if Basque President Patxi Lopez is forced to call early elections following the decision by the Basque Popular Party to end their coalition with Lopez's PSOE government.

Both Rajoy and Rubalcaba also lost voter confidence with Rajoy's rating falling from 4.55 to 3.84 points, and Rubalcaba's falling from 4.25 to 4.11 points.

UPD leader Rosa Diez continues to be the most valued politician with ratings of 4.47 points. None of the 13 ministers in Rajoy's cabinet have a rating of over 4.31 points.