FILE PHOTO: Prime Minister-designate Saad al-Hariri talks inside the parliament building in downtown Beirut, Lebanon May 28, 2018. REUTERS/Mohamed Azakir/File Photo

BEIRUT (Reuters) - The Lebanese Shi’ite group Hezbollah said on Thursday it was up to Prime Minister-designate Saad al-Hariri to resolve a row over Sunni representation that has obstructed the formation of a new government.

Six months after a parliamentary election, the row has further delayed the formation of a national unity government that is expected to group most of Lebanon’s sectarian political parties.

Lebanon is in dire need of a government able to implement the economic reforms that the IMF says are needed to put its public debt on a sustainable path. Lebanon has the world’s third largest public debt as a proportion of the economy, and growth is stagnant.

A deal looked close last week when the Christian Lebanese Forces Party ceded ground to President Michel Aoun and his Free Patriotic Movement, settling a row over Christian representation that had been seen as the main obstacle.

But Hezbollah, a heavily armed group backed by Iran, is pressing for one of its allied Sunni members of parliament to be given a cabinet portfolio, reflecting their gains in the election. Hariri, Lebanon’s leading Sunni, has resisted.

“We believe that the key to the solution is in the hands of the prime minister designate,” said Hezbollah deputy leader Sheikh Naim Qassem.

“He is the one who can accomplish the government tomorrow, and he is the one who can postpone the government to another time,” he said in comments broadcast by al-Manar TV.

Though an ally of Hezbollah, Aoun has sided with Hariri in the row. Last week, Aoun said he wanted a strong prime minister and not to weaken Hariri. He also criticized the Sunni MPs allied to Hezbollah, saying they did not constitute a parliamentary bloc that could demand cabinet representation.