BEIRUT, June 4 (Xinhua) -- Lebanese caretaker Foreign Minister Gebran Bassil defended on Monday President Michel Aoun on a naturalization decree which granted 300 people citizenship, the National News Agency reported.

Bassil said the president and the foreign ministry are not "involved in any suspicious acts regarding the controversial naturalization decree issued last week."

Bassil called for a "serious and quick investigation to reveal any discrepancies," claiming that the uproar over the decree was part of a "campaign" against Aoun and his tenure.

A decree granting Syrians, Palestinians, Iraqis and other Arab nationals Lebanese citizenship was at the center of harsh political criticism pointed at Aoun as the president is the sole authority to grant the Lebanese citizenship according to the constitution.

Many suspect that bribery was possibly behind the decree's signature.

"The campaign we are witnessing now has clear goals which are to target the president and his tenure," Bassil said, pointing out that the PM-designate Saad Hariri and caretaker Interior Minister Nouhad Machnouk also signed the decree and were not targeted.

The minister stressed that the ongoing investigation will reveal if any fault was committed.

He called on the president, who is his father in law, to continue granting citizenship for "deserving cases as long as it is carried out in a transparent process."

Bassil added that individual naturalization should be granted to people with Lebanese mothers, stateless individuals and others whose citizenship would bring a perceived benefit to the country.