By Luis Jaime Acosta

BOGOTA, May 20 (Reuters) - Colombian presidential candidate Paloma Valencia said she would scrap the government's “total peace” policy and pursue a tougher security strategy against ‌armed groups if elected, marking a sharp shift from leftist President Gustavo Petro's approach.

“The ‌policy of total peace ends with me. Total security will begin,” Valencia, 48, told Reuters in an interview on Tuesday, ​adding she would reactivate arrest warrants and strengthen security forces in cooperation with the United States.

Valencia, the right-wing Democratic Center party candidate backed by former president Alvaro Uribe, opposes continuing peace talks with dissident factions of the former FARC rebels, the National Liberation Army (ELN), and criminal gangs such as the ‌Gulf Clan.

Petro's government has sought ⁠to negotiate with armed groups to end a six-decade conflict that has killed more than 450,000 people, but talks have yielded no results with less ⁠than three months left in his term.

Valencia's platform emphasizes security, including expanding the police and military by 60,000 personnel and resuming aerial spraying of coca crops using non-glyphosate herbicides which was restricted in 2015 over health ​concerns.

A ​three-term senator, Valencia faces a crowded field including leftist ​Ivan Cepeda and independent right-wing businessman ‌Abelardo De La Espriella.

"We would elect a female president for the first time. And that is a historic event that we must achieve," said Valencia, whose campaign has focused particularly on female voters.

Polls suggest a tight race for second place, which would determine who faces Cepeda, the candidate of the Historic Pact coalition, in a potential runoff.

ECONOMIC STANCE

On economic policy, Valencia favors boosting oil, ‌gas and mining output, including fracking with environmental safeguards, ​in contrast to Petro’s push to curb new fossil fuel ​development.

“We will promote exploration and production ​of oil, gas, coal, minerals and rare earths, while also ensuring environmental protection,” ‌she said, adding fracking would be excluded ​from the Amazon and ​high-altitude paramo ecosystems.

She noted that growth of 5% in the mining, energy and construction sectors could raise 30 trillion pesos ($7.9 billion) to fund social spending.

Valencia also proposed cutting income ​taxes, eliminating wealth and financial transaction ‌taxes, and backing the U.S.-led "Americas Shield" regional security initiative.

More than 41 million Colombians are ​eligible to vote in the presidential election on May 31.

(Reporting by Luis Jaime ​Acosta; Editing by Aida Pelaez-Fernandez and Chizu Nomiyama )