Esperanza Aguirre, one of the leading figures of Spain's ruling conservative Popular Party, announced Monday her resignation as head of the Madrid regional government and her withdrawal from electoral politics after 29 years.

Aguirre told a press conference that she is leaving the post of regional lawmaker and head of the Madrid autonomous community after 29 years in politics.

"It's a hard decision, very hard," she told a press conference, attributing the move to "personal matters," including her recent battle with breast cancer, and her conviction that "this is the right time."

Aguirre, who said her cancer appears to be in remission, let it be understood that while her illness influenced her decision, it is not her only reason for leaving office.

She said she informed the leader of the PP, Prime Minister Mariano Rajoy, of her decision early on Monday.

The premier told Aguirre of his appreciation and noted "her tremendous political career," for which she will always be one of "the great assets" of the PP.

Rajoy hailed Aguirre's announcement that she intends to go on working with the PP and said he would "continue to count on her enthusiasm, her convictions and her dedication to politics from wherever she chooses to do so from now on."

Ignacio Gonzalez, up to now vice president of the Madrid autonomous community, will serve as acting president until the Madrid regional assembly elects a permanent successor to Aguirre.

The PP holds a majority in the regional assembly.

Aguirre said her resignation means leaving the front line of Spanish politics, though she will continue to be active in some capacity.

She also said that "there's no going back. I've crossed the Rubicon."

Very moved, she said she was retiring with the impression that the PP has launched a great project and that she is taking this step to spend more time with her family.

She confessed to being proudest of having introduced bilingual education - in Spanish and English - into public schools of the Madrid region.

Esperanza Aguirre was the third president of the Madrid autonomous region, after Socialist Joaquin Leguina, who served from 1983-1995, and her PP colleague, Alberto Ruiz-Gallardon, who headed the admininstration from 1995-2003 and is currently justice minister in the Rajoy government. EFE