LONDON, July 18 (Reuters) - Germany's 10-year government bond yield briefly touched an 18-month high on trading platform Tradeweb on Tuesday after the firm switched the benchmark to an August 2027 bond from a February 2027 issue.

The yield on the euro zone's benchmark bond jumped to 0.581 percent when trading opened, having closed on Monday at 0.516 percent.

It touched the new high of 0.589 percent shortly after 0700 GMT on Tuesday before edging 2 basis points lower on the day by 0730 GMT. (Reporting by John Geddie, editing by Nigel Stephenson)