"US stocks have outperformed and are now close to our year-end price target with limited upside, while the backdrop for European stocks outperformance is intact," the US bank's strategists said in a cross-asset note.
They increased their overweight in European equities from 2 percent to 3 percent relative to the benchmark, and cut their US equities overweight to 1 percent from 2 percent.
The S&P 500 has shot up more than 9 percent since the start of October 2017, while Europe's STOXX 600 has managed less than a third of that return over the same period.
The cross-asset strategists kept their preference for equities over bonds, with credit the least favoured, in a late cycle environment they said was heading for a "tricky handoff" at the end of the first quarter with PMIs likely to peak and inflation potentially rising.
"We think the best 'reflation' plays lie in being overweight energy and financial equities," they added.