* Buys back average of 5 mln shares/day in April, vs 15 mln/day Jan-March
* Slowdown could help free up cash to pay for investment in Telekom Austria
* Share buyback rate nearly half the year-ago level
By Elinor Comlay
MEXICO CITY, April 29 (Reuters) - Billionaire businessman Carlos Slim's America Movil has slowed the pace of its average daily stock repurchases by a third since the end of March, according to data analyzed by Reuters.
It is not clear why the pace of repurchases by Latin America's biggest phone company has slowed. An America Movil spokeswoman declined to comment.
Some analysts have suggested that America Movil could trim its buyback program in order to help pay for its more than $3 billion planned investment to take control of Telekom Austria , announced last week.
The pace of repurchases in April dropped to an average of 5 million shares a day, compared with an average of 15 million shares a day in January through March, according to an analysis of filings with Mexico's stock exchange.
America Movil's share price has been under pressure since Mexico's government approved a constitutional reform last year aimed at introducing more competition to the phone markets the company dominates.
Shares of the company are down 13 percent since the end of last year.
America Movil shares ended 2013 up 2 percent, helped in part by a large buyback program, which over the course of the year saw the company spend $5.4 billion on its own shares.
To date this year, America Movil has spent 13.4 billion pesos ($1.02 billion) to buy back 976 million shares, according to analysis by Reuters. That was almost half the outlay of 25 billion pesos used to buy back 1.9 billion shares in the same period a year earlier.
Slim and his family are the company's biggest shareholders. A filing with the U.S. Securities and Exchange Commission in February showed Slim, his family, their controlled companies and foundations owned about 47.6 percent of America Movil's outstanding shares.
AT&T Inc, which also has a stake in America Movil, has recently been trimming its position. A filing with the U.S. Securities and Exchange Commission this month showed AT&T held about 8.36 percent of America Movil, down from about 9 percent at the end of last year.
America Movil is due to hold its annual shareholders' meeting before the end of Wednesday at which it will vote on raising its total buyback fund by 30 billion pesos. At last year's shareholders' meeting, the company increased its buyback fund by 40 billion pesos. ($1 = 13.0962 Mexican Pesos) (Editing by Matthew Lewis)