Podemos, the "extreme left" leaning fringe party, has been given a significant boost ahead of the 2015 Spanish general election following the prime minister's battle to win back the public's trust following corruption allegations.

After Health Minister Ana Mato resigned earlier this week, following an investigating judge accusing her of benefiting from a kickback scheme that has badly damaged the ruling Partido Popular (People's Party/PP), Mariano Rajoy delivered a strong statement to battle cries of crooked politics.

"I can understand the irritation and distrust of our citizens but suspicion should not be levelled at everyone. Most politicians are decent people. Spain is not corrupt," said Rajoy to lawmakers.

Rajoy presented two anti-corruption laws in parliament which aim to ban legal and corporate entities from making political party donations as well as stopping banks from cancelling individuals' debts.

However, opposition leader Pedro Sanchez of Partido Socialista Obrero Español (Spanish Socialist Workers' Party/PSOE) said Rajoy's party cannot recover from the scandal.

"You are in no position to regenerate Spain against corruption. You are not able or legitimate to lead," said Sanchez.

Both of Rajoy's proposed bills must be debated in Spain's lower house before being passed into law.

Mato resigned after authorities accused her of receiving cash, luxury goods, flights and gifts to her family, in exchange for favourable governmental treatment.

However, she maintains that she is innocent and that she has not been charged with any crime.

Podemos, which has been dubbed the 'Spanish Ukip' due to the relatively young party's surging popularity challenging the usual rotation in government between two incumbent groups, has drawn significant support from its anti-graft ticket.

Earlier this month, a Sigma Dos poll revealed Podemos, which was founded only 10 months ago, could claim around 28.3% of the votes in the Spanish elections next year, around four times more than the group received at the European elections in 2014.

The key poll also revealed Pablo Iglesias, the leader of Podemos - which means "We Can" in English - claimed the highest-rated leader position, which could signal a monumental break in the interchangeable power shifts between PP and PSOE.