UPDATE 1-U.S. sees British trade deal 'reasonably soon'

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LONDON, Oct 20 (Reuters) - U.S. Trade Representative Robert Lighthizer said on Tuesday he was "very pleased" with progress in negotiations with Britain over a trade agreement and predicted a deal "reasonably soon".

The United States and Britain launched negotiations on a free-trade agreement in May, vowing to work quickly to seal a deal as Britain completes its exit from the European Union.

Lighthizer, speaking by video link from Washington to a British government conference on transatlantic co-operation, said talks were taking place continuously despite being split into rounds, while hinting at some differences over future trade ties.

"These things take time ... but we are making great headway and we have got 30-some groups negotiating and negotiating bitterly right now," Lighthizer told the Atlantic Future Forum.

"I am optimistic across the board and I think that it is going to happen reasonably soon," he said, referring to a deal.

British trade minister Liz Truss, speaking by remote link to the same conference, said western port cities like Liverpool would benefit from a U.S. trade deal as Britain widens its gaze beyond a 45-year-old bias in favour of trade ties with the EU.

The tone of the comments by both politicians contrasted with a separate stand-off over Britain's future trade ties with the EU following its exit from the bloc in January.

The EU and Britain urged each other on Tuesday to compromise to avoid a disruptive Brexit finale.

Lighthizer, who has named the UK trade talks one of his top priorities for 2020, published objectives more than a year ago that sought full access for U.S. agricultural products and reduced tariffs for U.S. manufactured goods.

The two sides are seen at odds, however, over tariffs including steel and aluminium duties imposed by Washington in 2018. (Reporting by Tim Hepher Editing by Alison Williams and Mark Potter)