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Generate an appropriate single-sentence summary for the given text such that it includes the main topic of the text.

By Marianna SpringSpecialist disinformation reporter, BBC News The adverts show the Democratic Party challenger with an earpiece, and say that he refused to have his ears checked for devices prior to the debate. The Biden campaign rejected the claims. The Trump campaign adverts ask: "Why won't Sleepy Joe commit to an ear test?" and "Who is in Joe's ear?" Accusations that presidential candidates have received debate help via hidden hearing devices are familiar, albeit unproven. Such allegations have been levelled against both Republican and Democratic candidates in the past. Prior to Tuesday's debate, the rumour about Mr Biden's supposed earpiece was circulating on several social networks, and was being promoted by the Trump campaign. At least 15 versions The advertising campaign was launched after the debate, and also promotes two other baseless but widely shared rumours about Mr Biden. One suggested he asked for breaks during the debate, and another accused him of refusing a "drug test". The photo featured in the advert is not from Tuesday's debate. It was first shared online in September 2019. In a number of the adverts, it has been doctored to show Mr Biden wearing wireless Apple headphones. This was not the case in the original image. Some versions circle the ear featuring the headphone. By Wednesday evening, there were at least 15 different versions of the advert, and according to Facebook's Ad Library, they had reached at least 10 million users. Facebook has pledged to label posts containing voting misinformation and point users towards accurate information ahead of the election. However its policy does not involve fact-checking political speech, including in advertisements. The company declined to comment about the latest Trump ad campaign. Rumour origins Hours before the debate, the claims went viral on Facebook and YouTube. Identical memes were pushed by a number of popular Facebook pages with names such as US Conservative and Unhinged Left. They claimed "Joe Biden should be inspected for a hidden earpiece as well as submit to a drug test before the debate". These memes are subject to fact-checks - and some have had warning labels applied to them on Facebook. The claims were picked up by Fox News and other conservative news outlets. They were further amplified by supporters of QAnon, an unfounded a conspiracy theory that claims President Trump is fighting a secret war against elite Satan-worshipping paedophiles. Those who believe in QAnon are known for promoting political disinformation on social media which targets opponents of the president. They shared close-up pictures of Mr Biden's ears, alleging a listening device was visible. During the debate, some also shared photos of a fold in Mr Biden's shirt, claiming it was caused by a wire, and of a supposed device on his wrist, where he wears a rosary in memory of his late son Beau. Nothing new Conspiracy theories about secret listening devices have been recycled in presidential election campaigns for the past two decades. Democratic candidate Hillary Clinton faced similar unfounded claims ahead of the 2016 presidential election. In 2004, rumours circulated among left-wing sites and blogs that President George W Bush was being aided by a secret earpiece. None of those allegations were found to be true. Even if a candidate did wear an earpiece, any advantage would be questionable. As TV and radio presenters can attest, listening to someone while simultaneously talking during the back-and-forth of a live event is a difficult skill to master.
Solution: US President Donald Trump's re-election campaign is running hundreds of Facebook advertisements pushing an unfounded conspiracy theory that Joe Biden cheated during the first US presidential debate.
Why? This is a relevant summary for the given paragraph. It also contains explicit phrases from the given text

New input: By Jayne McCormackBBC News NI Political Reporter The President of the European Parliament, David Sassoli, said there would be no agreement without a backstop in some form. But on Wednesday, Prime Minister Boris Johnson ruled out an NI-only backstop. The UK is due to leave the EU on 31 October without a deal unless both sides can reach a compromise. Mr Sassoli was speaking at a press conference after talks between the European Parliament's political group leaders and EU chief Brexit negotiator Michel Barnier. The parliament is not directly negotiating with the UK, but will vote on any final Brexit deal. UK officials have been in Brussels for meetings this week with Mr Barnier's team. Mr Sassoli said "the signals we're getting are not indicating any [UK] initiative that would reopen the negotiations, and we're not happy about that". He outlined points to be included in a European Parliament resolution on Brexit, to be voted on by MEPs next week. What is the backstop? It has proved to be the most contentious part of the Brexit negotiations. It is the insurance policy to avoid a hard border between Northern Ireland and the Republic of Ireland after Brexit, unless and until another solution is found. Westminster MPs rejected the backstop and withdrawal agreement negotiated by ex-PM Theresa May, which would have kept all of the UK in a "temporary customs territory" with the EU and would have seen Northern Ireland also continuing to follow other EU rules. The Democratic Unionists (DUP) had opposed it, saying it would create a border down the Irish Sea and risk the future of the union. There had been speculation in recent days that the UK was considering returning to the idea of a Northern Ireland-only backstop, which had originally been proposed by the EU in the early stages of the negotiations in 2017. The DUP had insisted it and No 10 would not back such a proposal as it would not have "unionist consent". After talks with Boris Johnson on Tuesday, the DUP said it was exploring all-island "arrangements" on food standards and animal safety as part of a solution to replace the backstop. Mr Sassoli said the European Parliament's draft resolution would say "we are willing to go back to the original EU proposal" of an NI-only backstop. "You can't have an agreement without the backstop, it couldn't really be any clearer," he added. The resolution will also express MEPs' willingness to turn the political declaration on future EU-UK ties into "a legally binding document". 'Firmness and clarity' The next EU summit is due to take place on 17-18 October, just several weeks before the UK is due to leave the EU on 31 October. Mr Johnson has insisted he will not seek another extension to the deadline, and said the UK would be ready to leave with or without a deal. He has said he hopes a deal can be reached and that he has an "abundance of proposals" to replace the backstop - but has not detailed what they might be. The Irish government has said it would also be willing to look at a "Northern Ireland-specific solution". Mr Sassoli said the EU had "reached a moment where we need to express our positions with firmness and clarity". The parliament is willing to extend the deadline beyond 31 October "provided it's something done for overriding reasons", Mr Sassoli said, such as to avoid no deal or to hold a general election. The resolution will say that if the UK exits without a deal "it will be entirely the responsibility of the UK". What was the NI-only backstop? It would have kept Northern Ireland in the EU's customs union, which would have meant applying EU tariffs for goods entering NI from outside the EU customs union - including Great Britain. It would also have applied EU single market rules for goods and animal products in Northern Ireland. This would have got rid of the need for checks at the Irish border, but would have led to checks on goods passing between Northern Ireland and Great Britain. It was criticised by the DUP and other unionist parties for "creating a border in the Irish Sea" and posing a risk to the union. In February 2018, Theresa May said no prime minister could back such a proposal.
Solution:
The head of the European Parliament has said he is willing to revisit the proposal of a Northern Ireland-only backstop to break the Brexit deadlock.