Robert Fowler (right) and his aide Louis Guay were freed unharmed in April
A former UN special envoy to Niger who was kidnapped by al-Qaeda and held for four months has said he believes a high-level leak led to his abduction.
Robert Fowler, now a retired Canadian diplomat, told Canada's CBC he felt someone in the Niger government or even the UN "shopped" him to the militants.
He said only the Niger government and the UN knew his itinerary.
Mr Fowler and his aide were seized last December north-west of the capital, Niamey. They were released in April.
Niger and the UN have so far made no public comments on Mr Fowler's interview.
It remains unclear what led the kidnappers from al-Qaeda's North African wing to free the UN envoy and his guide Louis Guay, also a Canadian national.
The Canadian government has denied paying a ransom.
"I know somebody shopped me," Mr Fowler told CBC.
"Who could it be? It could be be the government of Niger. Could have been an al-Qaeda sympathiser in the UN office in Niger. In the UN office in West Africa. In the secretariat building in New York."
Mr Fowler was appointed to his UN post in 2008 in an attempt to start a peace process in the conflict between the Niger government and Tuareg rebels.
But he said the government of Niger and in particularly President Mamadou Tandja "hated my mission".
"It was clear from the first time I met him in August that he [Mr Tandja] was offended, annoyed and embarrassed by the fact that the secretary general of the UN [Ban Ki-moon] had seen fit to appoint a special envoy for his country."
Analysts say Mr Tandja has had a fractious relationship with the UN during his 10 years in power.
During a food crisis in 2005 when 3.5 million people were left hungry, he accused UN agencies of exaggerating the country's problems in order to get donor funds.
Mr Fowler also defended his decision to travel without security officials, saying that the area was designated as safe in a UN security report.
He was seized by gunmen on the N1 Highway near the Niger River along the border between Niger and Mali.
Al-Qaeda's North African wing claimed responsibility for Mr Fowler's abduction.
However, some reports suggested he was initially abducted by Tuareg rebels operating in the area.