They said they maintain a base case the U.S. central bank would not lower borrowing costs at all in 2019, however, if economic data remains "sufficiently strong" and "a not unfavorable outcome" on trade between China and the United States emerges from next week's G20 summit in Japan.

A couple of other primary dealers, or the top 24 Wall Street firms that do business directly with the Federal Reserve, said they had a strong conviction about a 50 basis-point rate decrease at the Fed's next policy meeting in about six weeks.

UBS economists changed their base case to a half-point rate cut next month after this week's policy meeting.

Barclays economists have been forecasting a 50 basis-point cut in July following data earlier this month that showed weaker-than-expected jobs growth in the services sector in May.

On Wednesday, the U.S. central bank said it was prepared to lower borrowing costs as early as July on signs of softening business activity due to trade tensions and persistently sluggish inflation.

Minneapolis Fed chief Neel Kashkari said the Fed should reduce interest rates by 50 basis points to boost inflation expectations which have fallen below the Fed's 2% goal.

Interest rates futures implied traders see 32% chance the Fed would lower rates by 50 basis points in late July, down from 39% late on Thursday but up from 0.4% a month ago, according to CME Group's FedWatch tool.

(Reporting by Richard Leong; Editing by Tom Brown)