European stocks posted tepid early gains Monday as merger news and a bullish session in Asia boosted sentiment even as investors maintained a cautious tone with the U.S. dollar as the political upheaval surrounding U.S. President Donald Trump shows no signs of abating.

The region-wide Stoxx Europe 600 index, the broadest measure of share prices, was marked little changed from its Friday close at 391.17 points in the opening hour of trading while Britain's FTSE 100 lead gainers with an early 0.36% advance.

Benchmarks in Germany and France, however, were also largely flat from their Friday closing prices after the opening hour of trading as investors remained in a broadly cautious mood despite renewed M&A vigour.

A $20 billion deal in the European chemicals space provided broader support for the sector, and lifted shares in Clariant AG (CLZNY)  to an all-time higher after it said it would combine with U.S.-based Huntsman Corp. (HUN - Get Report)  in an all-stock deal that will be worth $20 billion.

HuntsmanClariant will have sales of around $13.2 billion, the companies said, based on pro-forma 2016 sales and adjusted operating profit of $2.3 billion. The deal is expected to close before the end of the year, the companies said in a statement.

Clariant shares leaped more than 9.3% in Zurich to change hands at €22.78 each, an all-time high, giving it a market cap of around €7.5 billion ($8.37 billion).

Overnight in Asia, the MSCI Asia ex-Japan index, the regional benchmark, was marked 0.86% while Japan's Nikkei 225 ended the session with a 0.45% advance to 19,678.28 points, even with the dollar's weakness pushing the yen higher in overnight trading.

The dollar index, a measure of the greenback's strength against a basket of its global peers, traded modestly higher in Asia but remains welded near six-month lows of 97.35 as investors continue to worry about political developments in the United States and wonder what the next headline may reveal with respect to the ongoing investigations into ties between Russian officials, President Trump's electoral campaign and the White House.

More directly-related data will also likely add to the dollar's volatility this week, notably in the form of Trump's first budget, scheduled for Tuesday, and the second reading of U.S. GDP later in the week.

Global oil prices continued to rise overnight after a torrid week of trading for crude futures last week that saw U.S. prices pass the $50 mark amid increased bets that OPEC members and their allies are prepared to extend their 1.8 million in production cuts well into 2018.

WTI futures for July delivery -- the new front-month contract -- were marked at $51.05 per barrel, a 1.35% gain from their Friday close, while Brent contracts for the same month were seen at $53.99, a smaller 0.7% gain from Friday.

Early indications from U.S. futures prices suggest a modestly stronger open on Wall Street Monday, with the Dow Jones Industrial Average set to rise around 17 points, or 0.1%, at the opening bell and the S&P 500 likely to gain 1.75 points, or 0.07%, at the start of trading.


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