China National Chemical Corp (ChemChina) is said to be within reach of clinching a deal to buy Swiss agrochemical producer Syngenta for about 43.7 billion Swiss francs ($42.8 billion).

An announcement could come as early as today, Feb. 3, sources told news agencies. The reported acquisition price represents a 24% premium over Syngenta’s Feb. 1 close at 378.40 francs on the Zurich stock exchange.

If successful, this could be the biggest-ever acquisition by a Chinese company. Last year, Syngenta rejected a 449-franc-per-share bid from ChemChina and a 470-franc offer from Monsanto but the company has been under shareholder pressure to finally sell.

The Chinese company most recently bought plastics machinery manufacturer KraussMaffei for about $1 billion. In 2015 it paid $7.7 billion for Italian tire maker Pirelli.

A sale of Syngenta to ChemChina is regarded as the easiest to gain antitrust approval. The combination of the Swiss player’s portfolio with the Chinese company’s existing agrochemical business, Adama – picked up for $2.4 billion from Israeli’s largest agrochemicals player in 2011 – would still give it only a 19% market share.

In any scenario, with Syngenta under its belt, ChemChina would be in the top three world agrochemicals player.

With sales of $19 billion calculated for its agrochemicals arm, the planned Dow-DuPont merger would give rise to a new top-seeded player. Monsanto would be in second place, as Syngenta, expected to report an 11% fall in sales to well under $14 billion when presenting annual results today, is the likely third.

Without a Syngenta deal, Monsanto will remain top-heavy in seeds, a situation it sought to change with its own bid. With vastly different portfolios, each of the two world-leading companies had around $15 million in annual sales in 2014. Around 75% of the Swiss company’s product offerings are in the chemicals column.

A takeover of Syngenta would underpin Chinese President Xi Jinping’s efforts to boost the country’s agricultural output as a growing middle class consumes more grain-intensive meat.

Buying the Swiss player also would give China access to agricultural land abroad, as farmland in the People’s Republic is increasingly being converted to housing and golf courses. According to the World Bank, the country’s arable land has declined 6% over the past decade.

For Syngenta, a purchase by the Chinese company would improve access to emerging markets.

In both the ChemChina-Syngenta and Dow-DuPont deals, factors of uncertainty remain. Both could require divestments, possibly giving lower-ranked players such as BASF and Bayer a chance to buy and move up a notch.

Some reports suggest that the US government could seek to block the ChemChina buy as being not in the national interest. Interesting to watch will be whether the deal needs approval of the Committee on Foreign Investment, one analyst told the British newspaper Financial Times.

The committee has the power to review and then block any transaction that may raise national securities concerns, recently torpedoing the planned sale of Philips’ Lumileds business to a Chinese private equity group.