To date, T&A has provided Ogilvy PR with local insights while Ogilvy has provided help with specialist areas such as financial and technology public relations.
A deal is expected by the end of March this year.
The 10-year old agency, founded by former journalist Nguyen Thanh Son (pictured), now the company's managing director, has 54 staff with offices in Hanoi and Ho Chi Minh City.
T&A's capabilities include consumer PR, events management, sports marketing and corporate social responsibility. Key clients include Canon, SAP and a number of government-linked companies.