Updated

Poland's key opposition party is facing questions about its credibility after its leader took a vacation with a female party member during a crucial protest in parliament.

The issue threatens to tarnish the image of the pro-business Modern party and its leader, Ryszard Petru, at a time when Modern is the most popular party opposing the controversial policies of the ruling Law and Justice party. Poland is in a political crisis, with some opposition lawmakers occupying parliament since Dec. 16 to press for a change of course.

Petru has attended the protest, but this week he was photographed with a colleague on a plane going to Madeira.

Interior Minister Mariusz Blaszczak said Petru's holiday discredits him and the protest.