In pictures: Pyongyang as North Korea's highest political gathering begins

The congress is being held at the April 25 House of Culture

Rainy Pyongyang has come to a standstill as the rare North Korean ruling party congress begins, seen as a way for leader Kim Jong-un to cement his hold on power in the secretive country.

Floral decorations for the congress dot Pyongyang

North Korean and propaganda flags are a common decorative feature near the venue, and security is tight

Streets in Pyongyang are being fastidiously scrubbed

There is sparse traffic on the roads surrounding the hall

Buses are among the few vehicles allowed on the roads near the venue

Crowds have gathered at Kim Il-sung Square near the iconic Juche tower

Many are carrying pink and red bouquets

The flowers are being placed around the square