We're stronger together

After months of bitter campaigning, Bernie Sanders yesterday offered his long-awaited endorsement for Democratic presidential hopeful Hillary Clinton, saying he would work hard to help his former rival win the White House.

The joint appearance at a high school in Portsmouth, New Hampshire -- their first -- was the culmination of weeks of talks between the two campaigns aimed at unifying the party to most effectively take on Republican Donald Trump in November.

"She (Hillary Clinton) will be the Democratic nominee for president and I intend to do everything I can to make certain she will be the next president of the United States," Sanders told a cheering crowd, with Clinton at his side.

Putting aside the acrimony, Clinton thanked Sanders for his endorsement .

"I am proud to be fighting alongside you," she said. "We are stronger together."

In a statement, the Trump campaign said Sanders was now officially part of the rigged system he had criticized during his long primary battle with Clinton.

Clinton hopes the joint appearance will help her win over Sanders supporters. In recent Reuters/Ipsos polling, only about 40 percent of Sanders backers said they would back Clinton.

The appearance in Portsmouth concluded weeks of negotiations between the two camps as Sanders pressed for concessions from Clinton on his liberal policy agenda. It came after Clinton last week adopted elements of Sanders' plans for free in-state college tuition and expanded affordable healthcare coverage. Sanders also successfully pushed to include an array of liberal policy positions in the Democratic platform, which a committee approved on Saturday.