HELSINKI (Reuters) - Finland's government watchdog reprimanded Foreign Minister Timo Soini on Tuesday for taking part in an anti-abortion vigil during an official visit to Canada.

Soini attended the event in Ottawa in May with his deputy, who posted a picture on Twitter, prompting calls from the opposition for Soini's resignation.

Finland is known for pioneering gender equality. The law allows abortion and the government is committed to promote women's rights in its foreign and security policy.

Parliament is due in the coming days to hold a no-confidence vote brought by some opposition parties over Soini's behavior, but, despite some criticism from his government colleagues, it is unlikely to pass due to the coalition's majority.

Chancellor of Justice Tuomas Poysti, who supervises the legality of the actions of the government and president, said it was "problematic" for a minister, especially for one who communicates official foreign policy, to take a stance against abortion during a work trip.

"Under these kind of circumstances, the foreign minister should follow particular carefulness and considered abstinence in his statements ... so that his conduct would not give any reason for misunderstandings," Poysti said in a statement.

He added, however, that Soini, a Catholic, had not breached the law and would face no further action from the watchdog.

On Tuesday, Soini, who attended the event during his free-time on the official trip, defended his freedom of religion but said he would take the watchdog's conclusion seriously.

Soini has said he turned to Catholicism in 1988 because he considered Evangelic Lutheran Church of Finland too soft on female priesthood and abortion.

He is opposed to gay marriage and has repeatedly criticized abortion and commented on votes about abortion overseas.

His previous party, the Finns, was kicked out of the center-right government last year after it elected more radical anti-immigrant leaders.

It then broke apart as Soini and some other lawmakers formed a new group, the moderately national Blue Reform, to stay in the ruling coalition.

(Reporting by Jussi Rosendahl; Editing by Alison Williams)