deploy as war error

Tried to deploy as war

Created rest and soap war files and placed under webapps folder of tomcat server and started it  , the desired structure came off but when trying to check the soap response from web ui getting error 

Request fired from Chrome:

http://10.103.2.89:8080/soap/

HTTP Status 500 - com/eviware/soapui/mockaswar/MockAsWarServlet : Unsupported major.minor version 51.0 (unable to load class com.eviware.soapui.mockaswar.MockAsWarServlet)

type Exception report

message com/eviware/soapui/mockaswar/MockAsWarServlet : Unsupported major.minor version 51.0 (unable to load class com.eviware.soapui.mockaswar.MockAsWarServlet)

description The server encountered an internal error that prevented it from fulfilling this request.

exception

java.lang.UnsupportedClassVersionError: com/eviware/soapui/mockaswar/MockAsWarServlet : Unsupported major.minor version 51.0 (unable to load class com.eviware.soapui.mockaswar.MockAsWarServlet)
	org.apache.catalina.loader.WebappClassLoaderBase.findClassInternal(WebappClassLoaderBase.java:3129)
	org.apache.catalina.loader.WebappClassLoaderBase.findClass(WebappClassLoaderBase.java:1341)
	org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1827)
	org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1701)
	org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:494)
	org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
	org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)
	org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436)
	org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
	org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)
	org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
	java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146)
	java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	java.lang.Thread.run(Thread.java:701)