KRAKOW, Poland (Reuters) – A Polish archbishop on Thursday sought to reaffirm Christian family values at the heart of conservative President Andrzej Duda’s re-election campaign, saying foreign “ideologies” were undermining the institution of marriage.

Archbishop Marek Jedrazszewski delivered the message to hundreds of people gathered, despite social distancing rules amidst the coronavirus outbreak, for a procession in the city of Krakow to mark the Catholic Corpus Christi holiday.

“(Foreign) ideologies undermine the institution of marriage and the family and we find their echo frequently in our homeland,” Jedraszewski said. “This is even more painful because it puts us in clear opposition to more than 1,050 years of Christian tradition in our nation.”

Duda, an ally of the ruling right-wing nationalist PiS party seeking a second term at the polls on June 28, vowed on Wednesday to protect family values in part by banning education surrounding LGBT issues.

The PiS argues that lesbian, gay, bisexual and transgender (LGBT) “ideology” is an invasive foreign influence undermining traditional values in the staunchly Catholic nation.

Duda’s main opponent is liberal Warsaw Mayor Rafal Trzaskowski of the centre-right opposition Civic Platform (PO) party. He has drawn criticism from religious conservatives for introducing education about LGBT matters in Warsaw schools.

The PiS is keen to secure Duda’s re-election as it would cement its grip on power to complete reforms to the judiciary and media sectors that the European Union has challenged, saying they violate EU standards on democracy and rule of law.

Duda remains the frontrunner but his lead has shrunk as the coronavirus crisis has damaged the economy.

The Krakow archdiocese called on participants in the Corpus Christi gathering to respect social distancing rules, like wearing masks, but many did not do so, a Reuters witness said.

Poland has 28,201 confirmed cases of the COVID-19 respiratory disease and 1,215 deaths.