Turkey in March ratified Finland’s bid for membership of the North Atlantic Treaty Organization, but still objects to Sweden joining the alliance, as does Hungary.
Turkey has said Stockholm harbors members of militant groups it considers to be terrorists.
“Sweden has taken significant concrete steps to meet Turkey’s concerns,” Stoltenberg told reporters, referring to a constitutional change by Sweden and its stepping up of counter-terrorism cooperation with Ankara.
Stoltenberg’s talks in Istanbul with Erdogan took place a week after Erdogan extended his two-decade rule in an election.
The election coincided with protests in Stockholm, against both Erdogan and NATO, in which the flag of the Kurdistan Workers’ Party (PKK), outlawed in Turkey, was projected on to the parliament building.
Asked about Sweden’s chances of becoming a NATO member before a mid-July NATO summit in the Lithuanian capital Vilnius, Stoltenberg said there was time.
He said the next round of talks between officials from Finland, Sweden and Turkey would be in the week of June 12, but did not specify when. NATO defense ministers will meet in Brussels June 15-16.