Asian markets were mixed on Wednesday as investors looked to tariff talks between the U.S. and China later this week, with sentiments lifted by Wall Street's strong Tuesday session which saw the S&P 500 touch an all-time high.

Developments in U.S. politics overnight, which saw President Donald Trump's former personal lawyer Michael Cohen plead guilty in federal court, also took center stage.

Australia's ASX 200 closed 0.29 percent lower at 6,266, as sectors such as utilities and the heavily-weighted financials subindex traded lower.

The telecommunications sector was one of the few which closed in positive territory Down Under, up by more than 7.54 percent on the back of news that TPG Telecom was looking at a potential merger with its rival Vodafone Hutchison Australia. Hutchison Telecoms, which owns a 50 percent stake in Vodafone Hutchison Australia, confirmed the news in an announcement that "exploratory discussions" were happening between the two.

Following the news, shares of TPG surged and closed up by 21.62 percent.

In Japan, the closed higher by 0.64 percent at 22,362.55. South Korea's Kospi closed up by 0.14 percent at 2,273.33.

The Hang Seng index recovered from its earlier losses to trade higher by 0.53 percent at 3:13 p.m. HK/SIN. In the mainland China markets ended the trading day in negative territory, with the Shanghai composite down by 0.7 percent to close at 2,714.61 while the Shenzhen composite was lower by 1.139 percent at 1,454.51.

Nasdaq-listed Chinese biotech firm, Zai Lab, is planning a second listing in Hong Kong, sources told Reuters. If true, it will be the second U.S.-listed biopharmaceutical company in China to return to the Hong Kong markets following new listing rules.

U.S. futures fell on the back of the developments in American politics. The S&P e-mini futures were down 0.25 percent at 2,854.5 at 2:05 p.m. HK/SIN, indicating that Wall Street might potentially open lower in the next trading session.

Trump's former personal lawyer Cohen pleaded guilty on eight counts related to tax fraud, excessive campaign contributions, making false statements to a financial institution, and unlawful corporate contributions at a court hearing in New York. He could face more than five years in prison.

Two of the counts that Cohen pleaded guilty to appear to relate to Trump directly. Cohen admitted on Tuesday to making payments to two women at the direction of an unidentified candidate for political office who appears to be the president. Those payments, Cohen said, were made to influence the outcome of the election.

While Cohen didn't name Trump directly during the hearing, it was later confirmed by the Justice Department that the President was the unidentified candidate.

At the same time, Trump's former campaign chairman Paul Manafort was found guilty of eight criminal counts, including five counts of tax fraud. He was also found guilty of two counts of bank fraud and one count of failing to file foreign bank account reports.

Some investors say the news is unlikely to have a long term impact on the U.S. markets.

"I think we've seen in the past since the Trump election, often times these events are white-hot in terms of media coverage but often times the markets seems to, to muddle through these so that may well be the case here as well," Fritz Foltz, chief investment strategist at 3EDGE Asset Management, told CNBC.

Others say more of such revelations could "encourage the president to pick targets that he thinks he can beat up on."

If the president "continues down that road, then it's not going to be good for the stock market because the stock market simply does not like that sort of uncertainty," Scott Nations, president and chief investment officer of NationsShares, said on CNBC's "Squawk Box," citing the example of Trump's criticism of Federal Reserve Chair Jerome Powell earlier this week.

In an interview with Reuters on Monday, Trump criticized Powell saying he was "not thrilled" with the latter for raising interest rates.