Whistleblower Christopher Wylie has appeared before MPs to discuss his work at scandal-hit Cambridge Analytica as Facebook founder Mark Zuckerberg turned down an invitation to give evidence to Parliament on the row.
Mr Wylie sparked an international outcry when he revealed the firm had harvested Facebook data from more than 50 million users, which was used to influence voters in Donald Trump's 2016 presidential run.
MPs are due to debate allegations that Vote Leave exceeded spending limits during the EU referendum, after Mr Wylie and another whistleblower Shahmir Sanni spoke out about how it was run.
Foreign Secretary Boris Johnson appeared before MPs this morning following news of the mass expulsions of Russian spies from the US and other allies, to show their support for Britain over the Salisbury nerve agent attack.
Theresa May will also be grilled on the poisoning of Sergei and Yulia Skripal by some of the most senior backbench MPs later today.
Meanwhile, Brexit divisions will also be in the spotlight ahead of the one year countdown to exit day, with speeches from prominent politicians, including leading Brexiteer Jacob Rees-Mogg and pro-EU former cabinet minister Lord Patten.
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