France is clearly the larger of the two: about 635,064 km² km² against 239,616 km² km², roughly 2.7× at true size. Drag one onto the other on the map above to feel the gap.
Both sit in Europe, so this is a same-region comparison: the new Equal Earth map draws both with the same honest geometry, and the real gap is exactly the 2.7× you see above.
The old map muddied it further: Mercator inflates France about 1.9× and United Kingdom about 2.9×, so on a Mercator-style map this pair appears 1.7× apart instead of the true 2.7×.
United Kingdom fits 2× into France.