Ben Emmerson QC - Marina Litvinko's lawyer has severely criticised the government's decision. He will seek judicial review.
He calls it "a repeated catalogue of broken promises[...] disastrous catalogue of indecision at the heart of government. [The government] has been paralysed by indecision".
Mr Emmerson says his widow and her son have been treated with "utter contempt" and in "the ultimate shabby way". He called it a "catalogue of disrespect".
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The Chancellor will promise to fix a glitch, which means repayments continue to be taken for up to 12 months after the loan is paid off.
The proposal will see the introduction of a discounted railcard for 26-30-year-olds, as the government looks to lessen the cost of living.
The vessel went missing last week with 44 sailors on board.