BAGHDAD — The Iraqi government’s national reconciliation efforts suffered a new setback yesterday as the main Sunni political bloc announced it has suspended talks on ending its boycott because of disagreements over a Cabinet post.

The dispute flared on the eve of a key U.N. conference in Sweden where Prime Minister al-Maliki was expected to face pressure to shore up recent security gains by making progress on the political front, including reconciliation among Sunnis, Shiites, and Kurds.

The Sunni Accordance Front’s leader, Adnan al-Dulaimi, said the decision was triggered by Mr. Maliki’s refusal to let the bloc resume the leadership of the key Planning Ministry.

“The talks yielded nothing and the government’s response was not in line with our demands so we have decided to suspend them,” Mr. Dulaimi said.

A Shiite lawmaker, Ali al-Adeeb, who is close to the prime minister, played down concerns about the decision.

“I do not think it is a big step backward and I do not think it will lead to the total withdrawal of the Accordance Front from the government. The government has agreed on most of the names given by the Accordance Front,” he said.

The Sunni bloc, which comprises three parties that hold 44 of the 275 parliamentary seats, pulled its members out of the 39-member Cabinet in August, saying they were not getting enough say in decision-making.

Followers of the Shiite anti-American cleric Muqtada al-Sadr also left the government last year after the prime minister refused their demands for a timetable for the withdrawal of American troops from Iraq.