Johannesburg - South Africa's rand plunged as much as 2.5 percent on Tuesday as the dollar recovered globally and President Jacob Zuma survived calls from inside his party to step down over scandals that have plagued his presidency.

The main stock market index hardly moved on the day as gains in heavily weighted stocks such Naspers offset declines in mining and banking shares.

Read also: Investors worried Zuma will 'go for broke'

At 15h45 GMT the rand had weakened 1.49 percent to 13.9350 per dollar, recovering slightly after sliding to a session low of 14.0850.

Bonds also retreated, with the yield on the benchmark 2026 paper adding 9.5 basis points to 8.99 percent.

The rand rose to near three-week highs on Monday after two ratings agencies on the weekend affirmed the country's investment grade status and on media reports that Zuma faced a vote of no-confidence by the ruling party's executive committee.

But on Tuesday, the ruling African National Congress said it had reaffirmed its support for Zuma.

One analyst said Zuma's removal had not been priced in by markets and therefore the currency's move could not be entirely pinned on local politics.

“Today has been more about the pull back in the dollar, that's the trend driving emerging markets,” said senior economist at Nedbank Isaac Matshego.

Emerging market currencies also weakened when the greenback was lifted by unexpectedly stronger GDP print in the United States.

On the bourse, the blue-chip JSE Top-40 index ended broadly unchanged at 43,602 and the broader All-share index inched down 0.07 percent at 50,157.

Both indices are on track for their fourth straight month of falls with retailers among the worst performers as job losses and weak economic growth squeeze consumer disposable income while a slight recovery in commodity prices has boosted demand for mining shares.

“It has been a poor time to be invested in equity markets locally, unless of course you have held the line on the resource stocks,” said Vestact's portfolio manager Sasha Neryshkine.

Naspers was up 1.5 percent at R2 071, recouping some of the losses suffered in the previous session when Africa's biggest company by market capitalisation reported its one-third rise in half-year profit to analysts and reporters.

On the downside, Anglo American, the best performing stock on the blue chip index so far this year, fell 2 percent to R207 and rival BHP Billiton lost 2.1 percent to R229.

Trading volumes were low with more than 213 million shares changing hands, below last year's daily average of 296 million shares.

REUTERS