WARSAW: A group of Polish opposition MPs wore the rainbow colours of the LGBT flag in protest against President Andrzej Duda at his swearing in ceremony on Thursday.

The MPs, including from the leftist Razem party, wore bright colours and rainbow face masks in contrast to the more sober attire worn by other lawmakers at the event.

"The President of Poland should defend the rights of all citizens," Magda Biejat, one of the protesting MPs from Razem, wrote on Twitter.

Duda was widely criticised during the election campaign for railing against what he called "LGBT ideology", calling it a new form of communist indoctrination.

The president is supported by the governing right-wing populist Law and Justice (PiS) party, whose MPs applauded and chanted their support during the ceremony in the Sejm lower house of parliament in Warsaw.

Many opposition MPs and leading public figures skipped the ceremony, which coincides with a nationwide spike in COVID-19 infections including among politicians.

The presidential election was due to be held in May but had to be postponed to July 12 because of the pandemic.Duda won a narrow re-election victory with 51 percent and was sworn in for a new five-year term on Thursday.

Duda said the election had been "difficult" but also "democratic, fair and very efficient", despite criticism from the opposition and international observers who said his campaign was helped by support from state media.

Thursday's ceremony comes a day after Polish police charged three people for draping rainbow flags over several statues in Warsaw last week, including one of Jesus Christ.

The three have been charged with desecrating monuments and offending religious feelings and face up to two years in prison if prosecutors proceed with the case.