Veteran B.C. MP and former federal NDP leadership candidate Nathan Cullen has endorsed Jagmeet Singh in the current race to pick a replacement for Tom Mulcair.

Cullen, who represents Skeena-Bulkley Valley in northern B.C., and Ontario MPP Singh made the announcement during a Wednesday morning news conference in Ottawa.

Cullen, who finished third in the 2012 race won by Mulcair, said Singh has a broad appeal and strong social democratic values, while adding it was a tough decision with three other strong candidates in contention.

"We have a candidate here who … ticks all the boxes for me," Cullen said.

"[He has an] ability to connect with people [and] ability to hold policies he believes in and manifest those policies as opposed to just saying something to get elected."

Singh said he has been watching Cullen's career and work with "incredible admiration," and it's an honour to have his support.

Singh and Cullen said they did not talk about Cullen getting a position in the party or certain policies promoted because of his endorsement.

NDP MP Nathan Cullen endorses leadership candidate Jagmeet Singh and says the fact that Singh doesn't hold a seat in parliament will not hinder his party. 1:51

As for comments from Mulcair, that it would be "a heck of a lot better" to have the next leader hold a seat in the House of Commons, Cullen said the party didn't get out of the Ottawa bubble enough last election.

Singh has said he's not concerned about not having a seat on Parliament Hill and that he can use the time to meet Canadians and rebuild the party's support.

New leader named in October

The first round of voting is underway.

Singh, Ontario MP Charlie Angus, Manitoba MP Niki Ashton and Quebec MP Guy Caron are the remaining candidates.

Singh has also been endorsed by former leadership candidate Peter Julian, who dropped out of the race this summer.

Ashton's endorsements include former 2012 leadership candidate Roméo Saganash, while former federal NDP leader Alexa McDonough has backed Caron and former Alberta NDP leader Ray Martin is supporting Angus.

A new leader could be chosen as early as Oct. 1, after the first round of voting.

If nobody gets enough votes in the first round, there will be one or two more rounds of voting.

The latest a new leader can be named is Oct. 15.