FTSE 100-listed Relx, which lost 117 million pounds through the exhibitions division in the first half, also reported underlying growth of 1-3% so far this year in the other businesses which make up the bulk of its revenues.
It expected modest growth in its legal and scientific, technical and medical operations while risk and business analytics were currently running at around 3% growth, roughly half the pace seen in previous years.
Shares in the company, down nearly 14% this year, dipped around 0.7% in morning trading, roughly in line with the broader stock market in London.
Relx is the world's second biggest exhibitions organiser and, like rival Informa, has been hammered this year by the COVID-19 pandemic and resulting travel curbs and other restrictions.
The company forecast annual revenue from the unit would be 330-360 million pounds, down from 1.27 billion pounds in 2019, and compared to costs estimated at 530-540 million pounds.
In comparison, it had booked 7.87 billion pounds in revenue in fiscal 2019, a 4% increase from the preceding year, with exhibitions making up just 16% of the total.
In its trading update, the company said event activity had reopened in a limited number of countries.
"Exhibitions are now running in China, Japan and a few other countries. Although revenue from most events is lower than from prior editions, satisfaction measures for both exhibitors and visitors are generally higher," Relx said.
The company, formerly known as Reed Elsevier, previously hosted more than 500 exhibitions in about 30 countries, attracting over 7 million people each year.
Relx vs FTSE 100:
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(Reporting by Patrick Graham and Muvija M in Bengaluru; Editing by Rashmi Aich and Bernadette Baum)