TPG Telecom has lifted its stake in Amcom Telecommunications to 19.9 per cent, making it harder for Amcom to win approval at next week's shareholder meeting for its planned merger with Vocus Communications.

TPG Telecom has lifted its stake in Amcom Telecommunications to 19.9 per cent, making it harder for Amcom to win approval at next week's shareholder meeting for its planned merger with Vocus Communications.