At 9.03am, the country's key index was down 5.3 points to 1,606.95.
Axiata was down 12 sen to RM3.99 and Digi fell 13 sen to RM4.33, leading the drop on the market.
There was also weakness seen in other blue chips, including Tenaga Nasional down four sen to RM10.20, Hong Leong Bank sliding 14 sen to RM18.38 and Petronas Gas down 26 sen to RM15.84.
While attention has shifted to the telco sector of late owing to news of a merger's between Axiata's Celcom and Digi, there has been renewed attention on healthcare counters given the rising nummber of Covid-19 cases despite the vaccine rollout.
Top Glove was up nine sen to M5.32, continuing to run higher following assurances that it was working towards resolving the import ban by the US Customs and Border Protection.
Hartalega rose four sen to RM9.96 and Supermax climbed 13 sen to RM4.70.
"After staying above the 1,600 level for the third session, we believe the FBM KLCI may trend higher for the week," said Malacca Securities Research.
It added that resistance is pegged at 1,615-1,635 while support is set at 1,565-1,575.
On the broader market, top active stocks include Daya up one sen to 2.5 sen, Luster rising 0.5 sen to 26 sen and UCrest rising one sen to 26.5 sen.