On the tape, cell members indicated they could get the weapons from the criminal, but cell leader Irfan Naseer said he couldn't approach the "gangster" because "he knows what I want to do," The Daily Telegraph reported Friday.
The al-Qaida-inspired cell in Birmingham is accused of plotting to use eight suicide bombers to detonate explosives-filled backpacks in crowded places to cause "mass death" and carnage.
Naseer, 31, Irfan Khalid, 27, and Ashik Ali, 27, all from Birmingham, allegedly are the cell's "senior members" and were among 12 people arrested and charged last year, the Telegraph said. The three said they are innocent of the charges that include planning a bombing campaign, recruiting others for terrorism and terrorism fundraising.
Woolwich Crown Court heard one police-recorded conversation in which the group discussed how to obtain weapons.
On the tape, Naseer was heard as saying: "You can buy M16, you can buy AK [assault rifle AK-47]. ... You can get grenades, you know grenades?"
On Thursday, the jury heard how the group talked about getting guns and storming a synagogue and other places. They also discussed killing 1,000 people by adulterating hand cream with poison and then rubbing it onto handles of cars and doors.