The rate at which banks charge each other to borrow yuan in Hong Kong surged to a record high Tuesday with speculation China's central bank was buying huge amounts of the unit to fend off speculators.

The overnight Hong Kong Interbank Offered Rate (HIBOR) for the offshore yuan jumped 53 percentage points to almost 67 percent owing to tight liquidity. The one-week rate also surged, to 33.8 percent from 11.2 percent.

Former German chancellor Gerhard Schroeder held talks Monday with top officials in Tehran on boosting trade links and Iran's diplomatic crisis with Saudi Arabia.

The visit comes ahead of the expected implementation of a nuclear deal with Iran that will open its economy to Western investment after years of sanctions on its banks and key industries.

David Bowie was not just a musical visionary, he also made history on financial markets two decades ago when he rocked Wall Street with a "celebrity bond", raising $55 million.

In 1997, the British singer launched the securities backed by the royalties to all his pre-1980 albums, which included smash hits "Let's Dance" and "Hunky Dory".

Moody's Investors Service on Monday downgraded Malaysia's sovereign outlook from "positive" to "stable", citing deepening economic woes from falling oil prices and global economic uncertainty.

In a statement, the ratings agency said the country faced slowing growth and world market factors that have "undermined Malaysia's external position, with large capital outflows, a falling current account surplus, sharp exchange rate depreciation and falling reserves." 

China's stock market resumed its volatile plunges on Monday, as worries over the slowing economy and the government's ability to manage it sent traders fleeing, dealers said. 

Investors have been alarmed by slowing growth in the world's second-largest economy, which is expected to have expanded last year at its slowest pace in a quarter of a century. Official data on fourth-quarter and annual growth is due to be released next week.

Oil prices fell further Monday on persistent worries about China's growth slowdown and a supply glut, but analysts said tensions between producer giants Iran and Saudi Arabia could provide some support.

U.S. benchmark West Texas Intermediate for February delivery was down 65 cents at $32.51 by 0600 GMT, while Brent was down 75 cents at $32.80.

Volkswagen chief executive Matthias Mueller will face a skeptical U.S. public on Sunday for the first time since American regulators accused the German automaker of cheating emissions tests.

VW's "apology tour" is expected to be a sharp contrast from the exuberance displayed by its competitors when the Detroit auto show formally opens Monday amid record-breaking U.S. sales.

China's consumer inflation rate crept higher in December, official data showed Saturday, as the world's second-largest economy struggles with slower growth.

The consumer price index (CPI) -- a main gauge of inflation -- rose 1.6 percent last month from a year ago, the National Bureau of Statistics (NBS) said in a statement, in line with the median forecast in a Bloomberg survey of economists.

State-owned Saudi Aramco, the world's largest crude oil producer and exporter, said Friday it is considering a public share offer.

The company "has been studying various options to allow broad public participation in its equity", a statement said.

Samsung Electronics on Friday flagged a 15 percent increase in 2015 Q4 operating profit, rounding off a year in which the world's largest smartphone producer struggled with fierce competition from arch-rival Apple and cut-price Chinese competitors. 

In an earnings estimate, the South Korean tech giant predicted an operating profit of 6.1 trillion won ($5.1 billion) for the October-December period, up from 5.4 trillion won a year earlier.