Guniean President Alpha Conde escaped two gunfire and rocket attacks on his residence in the capital Conakry on July 19 that killed at least three people and left his home riddled with bullets.
"I think the Senegalese government was complicit and so was the Gambian government, even if they say they were unaware," Conde said in an interview with private Senegalese radio broadcaster Sud FM.
He said he believed that the attacks on his residence were planned at one of Senegal's top hotels, the Meridien President, where his chief political rival Cellou Dalein Diallo stays when he is in Dakar.
"I told (Senegal foreign) minister Madicke Niang and the Gambian foreign minister that I believe this (attack) was planned at the (Meridien) President Hotel in Dakar and that there was a lot of back and forth with Gambia," he said. "This could not have been done without their knowledge."
Guinean authorities arrested 39 people in connection with the attacks, including 26 Guinean army officers.
The assaults in July raised concerns about stability in the West African state, the world's top bauxite supplier whose iron ore deposits have drawn billions of dollars in planned investment.
Conde was elected in late 2010 in a tight race with Diallo in a poll billed as the country's first free vote since independence from France, ending nearly two years of junta rule.