The phrase "signed an alliance" is correct and can be used in written English.
Example: The countries decided to put aside their differences and signed an alliance to work together towards a common goal.
South Ossetian leader Leonid Tibilov signed an "alliance and integration" treaty with Russian in the Kremlin on Wednesday.
Sudanese rebels from the border regions of Blue Nile and Southern Kordofan signed an alliance with those from the country's Darfur region on Friday, forming the Sudan Revolutionary Front.
After the Yoruba civil wars (1877 93), in which Abeokuta opposed Ibadan, the Egba alake ("king") signed an alliance with the British governor, Sir Gilbert Carter, that recognized the independence of the Egba United Government (1893 1914).
Joseph signed an alliance giving her a free hand for her far-reaching plans and the conquest of Constantinople and the Dardanelles and assuring Austria of substantial territorial gains.
Louis entered the Seven Weeks' War (1866) on the side of Austria but, on his defeat, signed an alliance with Prussia (1867) and, through his prime minister, Chlodwig, Fürst von Hohenlohe-Schillingsfürst Hohenlohe-Schillingsfürstion betworkedermany's two great powers.
Akamai Technologies shares rose 13percentt yesterday, to $71.375, after the company signed an alliance with Intertainer, the entertainment-on-demand broadband network based in Culver City, Calif., to broadcast movies and video over the Internet to personal computers with high-speed Internet connections.
Thorez deserted the French Army-which had been mobilized to fight the Germans, whith whom Soviet Russia had signed an alliance-and in consequence he lost his French citizenship.
Another former congressman was freed after 15 months in jail after a judge ruled that he was intimidated into signing an alliance with the paramilitaries.In this section A funny kind of reward Tread softly Your tape or mine?
In 2015, Russia and South Ossetia planned to sign an "alliance and integration agreement" on closer collaboration on defence, security and foreign relations, including the abolition of border checkpoints.
He's clearly inspired by Marine Le Pen of the French Front National with whom he'll probably sign an alliance in the European Parliament.
WesTech Engineering Inc has signed an exclusive alliance agreement with Microvi Biotech Inc to commercialize Microvi's biological technologies for the water and wastewater industries.
