SOFIA, May 29 (Xinhua) -- Bulgaria's President Rumen Radev on Monday asked the We Continue the Change - Democratic Bulgaria (PP-DB) coalition, the country's second-largest force in parliament, to form a government.

Radev handed the exploratory mandate to Nikolai Denkov, the PP-DB's nominee for prime minister.

"In the coming days, we will be negotiating with the other parliamentary forces in order to be able to form a regular government," said Denkov, whose coalition holds 64 seats in the 240-member parliament.

"I hope this sincere effort of ours will be supported," Denkov said.

Denkov has seven days to propose a government, which will then need the backing of parliament in a simple majority vote.

Radev first entrusted on May 15 the task of forming a new government to the GERB-UDF coalition, the country's largest political force, which holds 69 seats, but it failed to secure a parliamentary majority.

Should the PP-DB also fail to form a government, the president shall entrust the task to one of the four minor parliamentary groups. If no agreements can be reached, the president will call new parliamentary elections.