Britain warns Russia over Ukraine: we're working on high-impact sanctions

FILE PHOTO: British Foreign Secretary Liz Truss speaks during a G7 foreign and development ministers session with guest countries and ASEAN nations on the final day of the summit in Liverpool, Britain December 12, 2021. Olivier Douliery/Pool via REUTERS/File Photo

LONDON (Reuters) -Britain warned Moscow on Thursday that it was working with Western partners on high-impact sanctions targetting Russia's financial sector should it invade Ukraine.

Russia has massed some 100,000 troops near Ukraine's border and though Moscow says it has no plans to invade its neighbour, President Vladimir Putin has demanded legally-binding guarantees that NATO will not expand further eastwards.