Top German politicians were greeted on Monday by hundreds of right-wing anti-Islam protesters upon arrival to an East German city for Unification Day celebrations.

Protesters from the Patriotic Europeans Against the Islamisation of the West (PEGIDA) movement declared Chancellor Angela Merkel, President Joachim Gauck and Bundestag Parliamentary President Norbert Lammert "traitors to the public" as the politicians arrived for the 26th anniversary of German Unification celebrations in Dresden.

German police said on Twitter that they had to contain the protesters, many who were holding "Merkel must go" signs, so that the officials were able to attend the events.

Merkel, Gauck and Lammert signed the Golden Book of Dresden before attending a religious service and the main celebrations at the Semperoper opera house.

Unification celebrations this year have been marked by discussions on an apparent rise in xenophobia in East Germany, where the far-right Alternative for Germany party (AfD) has seen its biggest gains.

German Unification Day is a national holiday commemorating the reunification of East and West Germany in 1990.

PEGIDA, which originates from Dresden, has been organizing anti-Islam rallies on Mondays.