NEW YORK (CBSNewYork/AP) — Mayor Bill de Blasio and his predecessor, former Mayor Michael Bloomberg, are planning to make peace.

De Blasio and Bloomberg will hold a joint news conference on Wednesday of next week in the Bronx, to plant the millionth tree of the Million Trees NYC program that Bloomberg launched in 2007 to improve the quality of life on the city’s streets.

The meeting, several months in the making, is intended to bring the two together for a public fence-mending, two people briefed on the plan but not authorized to speak publicly on the matter told The Associated Press on Thursday.

De Blasio invited Bloomberg to join him two years after the then-public advocate was elected on the back of a fierce campaign that frequently criticized the billionaire incumbent for presiding over a city pockmarked with racial and economic injustice.

Those criticisms continued at the Democrat de Blasio’s January 2014 inauguration — at which one speaker likened Bloomberg’s New York to “a plantation” as the former sat mayor a few feet away — and early in the current mayor’s term.

Bloomberg had been a Democrat, but ran as a Republican and later became an Independent. He served three terms.

He pledged before leaving office that he would refrain from publicly criticizing his successor and has largely kept his word even as some of his allies, including former Police Commissioner Raymond Kelly, have taken loud umbrage at de Blasio’s attempts to reverse some of Bloomberg’s policies.

Early in his term, de Blasio also missed few chances to criticize Bloomberg for creating a “Tale of Two Cities” in which the gap between the rich and the poor grew, de Blasio believes, because of his billionaire predecessor’s Manhattan-centric policies.

But the mayors’ relationship has shown signs of thawing in recent months. De Blasio has softened his rhetoric about Bloomberg and has taken pains to compliment his predecessor’s policies on climate change and gun control and his successful push to win mayoral control of the city’s school systems.

It was a top Bloomberg aide, Howard Wolfson, who suggested to the de Blasio administration that the city throw a ticker-tape parade for the World Cup-winning women’s soccer team. Conversations between the two men’s staffs have also increased in recent months, and de Blasio and Bloomberg chatted amiably at this year’s 9/11 memorial service.

They also appeared together in June at the groundbreaking for the Cornell Tech campus on Roosevelt Island and traded some sincere, if somewhat restrained, compliments. But the event next week is to be explicitly a display of outreach from one mayor to the other, according to the people briefed on the plan.

Bloomberg also remains popular with some pockets of New Yorkers, and aides to de Blasio, whose poll numbers are middling, could see the political advantages of a stronger relationship with the media mogul. The move also comes amid a shift in City Hall’s strategy with the mayor’s public events, putting him in front of constituents more and reporters less.

Representatives for Bloomberg and de Blasio did not immediately respond to a request for comment.

De Blasio has wildly differing relationships with the other two living New York City mayors. Republican Rudy Giuliani has emerged as a fierce critic of the current mayor, particularly on policing issues. But de Blasio enjoys a warm relationship with Democrat David Dinkins, his former boss, and presided over a ceremony renaming a government building for Dinkins on Thursday.

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