Jeremy Corbyn Labour leader
The challenge starts now for Jeremy Corbyn after becoming Labour's new leader Reuters/Neil Hall

Jeremy Corbyn has been thrown in the deep end after riding a tidal wave of left-wing support to be crowned the new Labour leader. The socialist got to work almost immediately on forming a shadow cabinet as a number of high-profile reds, including Tristram Hunt and Rachel Reeves, quit the frontbench.

Corbyn gave the top economic job to his close ally John McDonnell, who succeeds Chris Leslie as shadow chancellor. Elsewhere, the left-wing leadership secured a coup by keeping Rosie Winterton as chief whip, but Corbyn was dealt another blow when shadow energy secretary Caroline Flint stepped down.

The 66-year-old has also been thrown into a gender row because of the apparent lack of women in Labour's top jobs. But Corbyn's team has hit back, claiming the positions of shadow education secretary (filled by Lucy Powell) and shadow health secretary (taken up by Heidi Alexander) are high-ranking roles.

"For Labour our proudest achievement is the creation of the NHS. We are the party that delivered comprehensive education. We are the party that founded the Open University, and that established and will defend trade union and employment rights," the statement read. "The so-called 'great offices of state' as defined in the 19th century reflect an era before women or workers even had the vote, and before Labour had radically change the state."

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The union test

The row comes as MPs are debating the government's controversial Trades Union Bill in the House of Commons. Corbyn has vehemently opposed the draft legislation, which would enforce a 50% minimum threshold on strike ballots.

Chuka Umunna was expected to take the fight to the Tories over the bill in parliament on 14 September but the former shadow business secretary resigned from the front bench after a "mutual agreement" with Corbyn the night before the crunch vote.

Angela Eagle, who was beaten by Tom Watson to become deputy leader, has now been appointed to Umunna's old job. The Wallasey MP will now face down business secretary Sajid Javid in the Commons. The pressure is on Eagle after Corbyn had very strong union support during his campaign and the leader is expected to give a speech at the Trades Union Congress (TUC) conference in Brighton on 15 September.

One-on-one with Cameron

But the Trades Union Bill could be a minor test in the public's eye when it is compared to Prime Minister's Questions. Corbyn will want to put in a solid performance against David Cameron when the two leaders battle it out across the historical dispatch boxes of the Commons. The prime minister has a quick wit and was able to easily repel Miliband during their exchanges.

Cameron could mock and taunt Corbyn at PMQs but Michael Gove gave a hint over the weekend at the approach the Conservative leader may take. The justice secretary said he was "sombre and respectful" of Corbyn's democratic mandate but the top Tory went on to warn that the left-winger was a risk to national and economic security.

The line was repeated by the Tories on 14 September when they launched an attack advertisement on YouTube. The film focuses on Corbyn calling Osama bin Laden's death a "tragedy" and describing terror groups Hamas and Hezbollah as "friends".

Corbyn has remained cool for the most part while under fire, but there are a few instances when the leader has become testy while being pressured by journalists, notably when he lost his temper on Channel 4 News in July. Can Cameron get under his skin?