On the eve of Pope Francis’s arrival in the U.S., the Vatican has taken offense at the Obama administration’s decision to invite to the pope’s welcome ceremony transgender activists, the first openly gay Episcopal bishop and an activist nun who leads a group criticized by the Vatican for its silence on abortion and euthanasia.

According to a senior Vatican official, the Holy See worries that any photos of the pope with these guests at the White House welcoming ceremony next Wednesday could be interpreted as an endorsement of their activities.

The tension exemplifies concerns among conservative Catholics, including many bishops, that the White House will use the pope’s visit to play down its differences with church leaders on such contentious issues as same-sex marriage and the contraception mandate in the health care law.

The White House didn’t respond to requests for comment on the Vatican’s reaction to the ceremony’s guest list. White House press secretary Josh Earnest told reporters Thursday he was unaware of the names of individuals on the guest list, but cautioned against drawing any conclusions on specific guests “because there will be 15,000 other people there too.”

In the last few days, several people have acknowledged or made public their receipt of invitations to the event, which will be held on the White House’s South Lawn on the morning of Pope Francis’ first full day in the U.S.