N. Korea's first ruling party congress since 1986

The party announced the convention on Friday, just weeks after it celebrated its 70th anniversary with a lavish military parade (pictured). It will be the party's seventh congress since the party was formed.

A statement, released by the North's official KCNA news agency said the country was faced with "the heavy yet sacred task" of building a "thriving" nation.

Exactly what will be discussed remains unclear, however, with the dispatch saying only that the congress will "further strengthen the party ... and enhance its leading role."

Observers said the convention would provide North Korean leader Kim Jong-Un with the chance to signal any significant policy shifts or reshuffle the party leadership, as seen at previous party congresses.

Three decades since last congress

The Workers' Party last held a congress in October 1980, under North Korea's founding leader Kim Il Sung. His son and successor Kim Jong Il never called a congress, however.

Next year's meeting will therefore be a first for Kim Jong Un, who took power after the death of his dictator father in late 2011.

During his first four years as leader, Kim has struggled to revive the North's declining economy, while also dealing with an international standoff over his country's nuclear and missile programs.

North-South tension

A South Korean news report said on Friday that North Korea is digging a new tunnel at its nuclear test site.

"The fact that they are constructing a new tunnel indicates the intention is to conduct a nuclear test at some point," the source was quoted as saying. There was no evidence to conclude the preparation was for an imminent test, the source added.

More than 60 years since the two countries called an armistice, relations with the South continue to be strained.

ksb/kms (Reuters, AFP, AP)